Early Photographic Synchronization System and Method

ABSTRACT

A system and method for synchronizing a photographic lighting device to image acquisition by a camera such that initiation of light emission of the photographic lighting device occurs after the first shutter blade of the camera begins to expose an image acquisition sensor of the camera to light and before X-sync associated with the first shutter blade stopping movement.

RELATED APPLICATION DATA

This application claims the benefit of priority of U.S. ProvisionalPatent Application Ser. No. 61/152,089, filed Feb. 12, 2009, and titled“Early Photographic Synchronization System and Method, which isincorporated by reference herein in its entirety.

FIELD OF THE INVENTION

The present invention generally relates to the field of synchronizingphotographic lighting to image acquisition. In particular, the presentinvention is directed to an early photographic synchronization systemand method.

BACKGROUND

Conventional cameras produce a synchronization signal known as an“X-sync” signal. An X-sync signal is initiated when a first shutter ofthe camera moves to a fully open position during an image acquisition.In one example, a mechanical sensor detects the shutter blade coming toa stop in motion. An X-sync signal can be used to fire a flash device toemit light during an image acquisition. As discussed further below,cameras typically have a maximum shutter speed (e.g., “faster” shutterspeed that correlates to a shorter opening of the shutter) at whichsynchronization using X-sync can occur without “clipping” occurring inthe image. This shutter speed defines the maximum X-sync for a givencamera. Clipping is when flash lighting illuminates the imaging sensor(or alternatively film) unevenly due to light emission during a shutterblade traveling across the sensor. Clipping appears as a band of darkerexposure in the image (e.g., at the top or bottom of the image).

FIGS. 1 and 2 illustrate timing plots related to one example of aconventional photographic flash synchronization system and method for anexemplary camera having a two blade focal plane shutter system. In thisexample of FIG. 1, the shutter speed is set at a relatively slowershutter speed setting (i.e., having a longer opening of the shutter)than the example discussed below with respect to FIG. 2. FIG. 1 includesa timing plot 105 showing mirror movement from an initial closedposition to an open position (i.e., a position blocking the light pathfrom the camera lens from the shutter mechanism to a position thatallows light to pass to the shutter mechanism). FIG. 2 includes a timingplot 205 showing mirror movement from an initial closed position to anopen position. Timing plot 110 of FIG. 1 and timing plot 210 of FIG. 2each show movement of the edge of the first shutter blade to travelacross an imaging sensor of the camera in the respective examples to aposition in which the first shutter blade allows light to pass to theentire imaging sensor. Timing plot 115 of FIG. 1 and timing plot 215 ofFIG. 2 each show movement of the edge of the second shutter blade totravel across the imaging sensor in the respective examples to aposition that blocks all light from passing to the imaging sensor. Ineach of plots 105, 110, 115, 205, 210, 215, the lower horizontal line ofthe plot represents a fixed position prior to movement, the upperhorizontal line of the plot represents a fixed position after movement,and the slanted line there between represents the time of movement.

In the example of FIG. 1, the time 127 between vertical dashed line 120and vertical dashed line 125 is the time in which both shutter bladesare in the fixed open positions allowing light to travel from the cameralens to the imaging sensor of the camera. In this example, during thetime between lines 120 and 125 the first and second shutter blades donot obstruct the light to the sensor. In some examples, the firstshutter blade of a camera will start movement at a time prior tobeginning to allow light to pass to the imaging sensor (i.e., thestarting position of the first shutter blade is at a distance from theedge of the imaging sensor) and the first shutter blade fully stopsobstructing light from passing to the imaging sensor at a time prior tothe first shutter blade stopping movement (e.g., at time 120). A cameramay have a distance between the edge of the imaging sensor and thelocation where the shutter blade comes to a stop (e.g., to preventdamage to the shutter blade due to an instantaneous abrupt stop).Likewise, the second shutter blade of a camera may start movement at aposition that is a distance from the edge of the imaging sensor suchthat it does not start to block light from passing to the imaging sensoruntil a time after the second shutter blade begins movement (e.g., attime 125) and the second shutter blade fully blocks light from theimaging sensor at a time prior to stopping movement. Dashed lines 130and 230 mark the time at which the second shutter blade in each example,respectively, stops movement.

In the example of FIG. 2, the time 227 between vertical dashed line 220and vertical dashed line 225 is the time in which both shutter bladesare in the fixed open positions allowing light to travel from the cameralens to the imaging sensor of the camera. In this example, during thetime between lines 220 and 225 the first and second shutter blades donot obstruct the light to the sensor.

The time between the first shutter blade of a camera stopping movementand the second shutter blade stopping movement (shown in the example ofFIG. 1 as time period 135 and in the example of FIG. 2 as time period235) may be referred to as the exposure time and is typically measuredas the shutter speed of the camera. Plots 140 and 240 show aconventional synchronization signal (commonly referred to as a “synch”signal or an X-Sync signal) of the examples of FIGS. 1 and 2,respectively. Synch signals 140 and 240 are indicated by a voltagechange at time 120 and 220, respectively, and a return to prior voltageat time 130 and 230, respectively. A conventional synch signal beginswhen the first shutter blade stops movement. In one example, a sensor inthe camera detects the first shutter blade coming to a stop and causesan electrical signal that initiates an X-sync signal. In one suchexample, there may be some additional movement of the first shutterblade after the activation of the sensor (e.g., due to the actuation ofa mechanical element of the sensor, due to bounce of the blade from theforce of slapping open). Such movement after the normal temporallocation for the activation of the X-sync signal of a camera is notincluded in the time determination for the stopping of the movement ofthe first shutter blade.

Plot 145 shows a plot of light emission over time from a photographiclighting device associated with the camera of the example of FIG. 1.Horizontal dashed line 150 marks the critical level above which thelight emission of the lighting device is detectable by the imagingsensor of the camera over ambient light. The hatched area under thecurve of the light emission profile represents light emission thatcontributes to the imaging by the camera sensor. Plot 245 shows a plotof light emission over time from a photographic lighting deviceassociated with the camera of the example of FIG. 2. Horizontal dashedline 250 marks the critical level above which the light emission of thelighting device is detectable by the imaging sensor of the camera overambient light. The hatched area under the curve of the light emissionprofile represents light emission that can contribute to the imaging bythe camera sensor. Light emission is initiated in response to the synchsignal. In the examples of FIGS. 1 and 2, a slight delay is shownbetween the sync signal and the initiation of light emission by thelighting device (e.g., possibly due to circuitry delay in the lightingdevice and/or time required to wirelessly transmit a light emissioninitiation signal to a lighting device that is remote from the camera).

The entire area above line 150 falls between line 120 and line 125during the time period 127 in which the first and second shutter bladesare not moving and the sensor is fully unobstructed by the two shutterblades. Thus, the light emission from the photographic lighting devicein the example of FIG. 1 with the relatively longer shutter speed doesnot contribute to imaging during the time when the shutter blades aretraveling across the imaging sensor. This is not true for the example ofFIG. 2 with the faster shutter speed. A significant amount of thedetectable light emission of the lighting device of plot 245 occursafter the second shutter blade begins movement and obstruction of theimaging sensor. This may cause uneven lighting of different portions ofthe imaging sensor and cause uneven darkening areas of the resultantimage (e.g., referred to as “clipping”). Due to this limitation of theconventional synchronization method, photography with flash lighting istypically limited to shutter speeds that are slower (i.e., longer) thana particular shutter speed. For example, many cameras cannot adequatelysynchronize flash lighting at shutter speeds greater than 1/200^(th) ofa second.

One way to allow for shorter shutter speeds includes utilizing rapidlypulsed light bursts of a lighting device to produce a pseudo-continuouslight source with a duration that spans from before initial shutterblade movement to well after final shutter blade movement. Such a systemutilizes a great deal of extraneous energy before and after the actualimage acquisition time period. This may result in excess depletion oflighting power sources. This type of synchronization is often referredto as “FP-sync.” It is also known in certain cameras manufactured byCanon as HSS, HS-sync, and/or “high-speed” sync. Herein, this type ofsynchronization is referred to as “FP-sync” and/or “FP-type sync.” FIG.3 illustrates timing plots associated with one such example of anFP-type sync process. Plot 310 shows the movement of the first shutterblade of a camera similar to plots 110 and 210 discussed above. Plot 315shows the movement of the second shutter blade of a camera similar toplots 115 and 215 discussed above. Dashed line 320 marks the time of thefirst shutter blade stopping movement. Dashed line 325 marks the time ofthe second shutter blade starting movement. The time 327 between lines320 and 325 marks the time period in which the first and second shutterblades are not moving and are in the fully open position allowing lightto pass to the imaging sensor of the camera. Dashed line 330 marks thetime of the second shutter blade stopping movement after the edge of thesecond shutter blade has traveled across the imaging sensor. The time335 between lines 320 and 330 represents the shutter speed. Plot 340shows a conventional sync signal as a voltage change starting at time320 to time 330. Plot 345 shows a photographic light emission profileintensity curve. Dotted line 350 indicates the start of movement of thefirst shutter blade. Light emission begins at a time prior to the firstshutter blade beginning movement. The light emission reaches a peak andthe lighting device is rapidly pulsed such that a pseudo-continuouslight emission level begins prior to the first shutter blade beginningmovement. This light emission must is held at this level until a timeafter line 330 (i.e., after the second shutter blade fully obstructslight from passing to the imaging sensor). This ensures a near constantlight emission above ambient light during all times that the imagingsensor is either partially or fully unobstructed by the shutter blades.However, plot 345 shows significant light emission over an extendedperiod of time. Such light emission may utilize a great amount of energyand possibly deplete lighting device power supplies.

SUMMARY OF THE DISCLOSURE

In one implementation, a method for synchronizing a photographiclighting device to image acquisition by a camera is provided. The methodincludes allowing a first shutter blade of the camera to move such thatlight is allowed to pass to an imaging portion of an image acquisitionsensor of the camera; and initiating light emission of the photographiclighting device after the first shutter blade begins to expose the imageacquisition sensor to light and before X-sync associated with the firstshutter blade stopping movement.

In another implementation, a method for synchronizing a photographiclighting device to image acquisition by a camera is provided. The methodincludes associating a photographic lighting device having a lightemission profile with an initial critical point and a terminal criticalpoint with the camera; and initiating light emission from thephotographic lighting device prior to the first shutter blade stopsmovement such that the initial critical point occurs at a point in timeafter about 1 millisecond before the first shutter blade moves to aposition that no longer obstructs light to the imaging portion of thesensor.

In still another implementation, a method for synchronizing aphotographic lighting device to image acquisition by a camera isprovided. The method includes detecting a predictor signal and/or event;determining an amount of time from the occurrence of the predictorsignal and/or event until a desired time for the initiation of lightemission of the photographic lighting device; transmitting to thephotographic lighting device an instruction for the initiating lightemission of the photographic lighting device at the desired time; andinitiating light emission of the photographic lighting device after afirst shutter blade of the camera begins to expose the image acquisitionsensor to light and before the first shutter blade stops movement.

In yet another implementation, a method for synchronizing a photographiclighting device to image acquisition by a camera is provided. The methodincludes identifying a camera predictor event and/or signal that occursprior to the first shutter blade of the camera moving to a point thatallows light to pass to the imaging portion of the sensor, the predictorevent and/or signal not being an event or signal intended forinstructing the initiation of X-sync, the predictor event and/or signaloccurring prior to the time of X-sync and based upon the occurrence ofthe predictor event and/or signal, communicating to the photographiclighting device an instruction for the initiating light emission of thephotographic lighting device.

In still yet another implementation, a method for synchronizing aphotographic lighting device to image acquisition by a camera isprovided. The method includes allowing a first shutter blade of thecamera to move such that light is allowed to pass to an imageacquisition sensor of the camera; and initiating light emission of thephotographic lighting device after the first shutter blade begins toexpose the image acquisition sensor to light and before the shuttertravel completion switch is detected by camera.

In a further implementation, a system for synchronizing a photographiclighting device to image acquisition by a camera is provided. The systemincludes means for allowing a first shutter blade of the camera to movesuch that light is allowed to pass to an imaging portion of an imageacquisition sensor of the camera; and means for initiating lightemission of the photographic lighting device after the first shutterblade begins to expose the image acquisition sensor to light and beforeX-sync associated with the first shutter blade stopping movement.

In yet a further implementation, a system for synchronizing aphotographic lighting device to image acquisition by a camera having animage acquisition sensor and a shutter system with a first shutter bladeis provided. The system includes a connection to a camera circuitryproviding access to a camera predictor signal; a memory includinginformation related to instructions for initiating light emission afterthe first shutter blade begins to expose the image acquisition sensor tolight and before X-sync associated with the first shutter blade stoppingmovement; a processor element configured to use the information and thecamera predictor signal to generate a lighting emission initiationsignal; and a connection to the photographic lighting device incommunication with the processing element for communicating the lightingemission initiation signal to the photographic lighting device.

DETAILED DESCRIPTION

A system and method for synchronizing a photographic lighting device toimage acquisition by a camera is provided. In one embodiment, lightemission by one or more lighting devices is initiated after a firstshutter blade movement of a camera begins to allow light to pass fromthe camera lens to an imaging sensor of the camera and before X-syncassociated with the completion of the first shutter blade movement.

As discussed above, there may be some additional movement of the firstshutter blade after the normal temporal location for initiation ofX-sync. When discussing completion of the first shutter blade movementwith respect to the timing of photographic light emission in embodimentsof the current disclosure, the stopping of movement being referred to isthat of the point of the normal initiation of X-sync for the camera. Ifthere is subsequent movement of the shutter blade, it is not consideredin determining the time at which the first shutter blade stops movementfor the determination of the time for initiating photographic lightemission prior to the completion of the first shutter blade movement.

FIG. 4 illustrates one implementation of a method of synchronizing aphotographic lighting device. At step 405, one or more photographiclighting devices are provided in association with a camera. Any one ormore photographic lighting devices may be utilized. Example photographiclighting devices include, but are not limited to, a flash deviceinternal to a camera body (e.g., a pop-up flash of a digital SLRcamera), a strobe, a studio flash pack, a speedlight (e.g., a hot shoemountable flash light), and any combinations thereof. In one example,one or more lighting devices associated with a camera include one ormore internal flash devices. In another example, one or more lightingdevices associated with a camera include one or more studio-type flashpacks (e.g., connected via wire to a camera and/or connected wirelesslyto a camera). In yet another example, one or more lighting devicesassociated with a camera include one or more hot shoe mountable flashdevices (e.g., connected directly and/or indirectly to the hot shoe ofthe camera and/or connected wirelessly to the camera).

At step 410, a first shutter blade of a camera begins to allow light topass to an imaging sensor of the camera. An imaging sensor has animaging portion that becomes exposed to light when the shutter of thecamera is fully open. The sensor itself may have additional surfacearea, portions, and/or components that are not exposed to light forimage acquisition when the shutter of the camera is fully open. When theterm “sensor” is utilized herein with respect to allowing light to passthrough the shutter to the sensor device, it refers to the imagingportion of the sensor.

At step 415, light emission of at least one of the one or more lightingdevices is initiated after the first shutter blade movement begins toallow light to pass to the imaging sensor and before the first shutterblade movement stops.

In one example, a first shutter blade movement is the movement of afirst shutter blade of a focal plane shutter having two shutter bladesthat move collaboratively to allow light to pass to an imaging sensor.In one such example, a first shutter blade moves to start allowing lightto pass (e.g., at the beginning of image acquisition) and a secondshutter blade moves to begin to obstruct light from passing to thesensor (e.g., to end image acquisition). In another example, a firstshutter blade movement is the first movement of a leaf shutter mechanismhaving two or more shutter blades that move together from a positionthat blocks light from passing to an imaging sensor to a position thatallows light to pass. As the one or more shutter blades begin the firstmovement an opening is created in the center area of the shuttermechanism and the one or more shutter blades move outwardly to a fullyopen position. For purposes of the discussion of shutter blades herein,the one or more shutter blades of such a shutter mechanism movingtogether in this first movement will be referred to herein as the firstshutter blade. The two or more shutter blades then begin a secondmovement together to close such that light is obstructed from passing tothe imaging sensor. For purposes of the discussion of shutter bladesherein, the one or more shutter blades of such a shutter mechanismmoving together in this second movement will be referred to herein asthe second shutter blade.

Initiation of light emission as used herein refers to initiation oflight emission for exposing the image acquisition. Such light emissiondoes not include incidental light emission, such as optical lightutilized by certain photographic equipment for focus assist, opticalwireless communication, and other non-exposure uses of light. Initiationof light emission may occur in a variety of ways. Ways to initiate lightemission include, but are not limited to, generation of a light emissioninitiation signal, initiating light emission of a lighting devicedirectly or indirectly connected to the camera via wired electricalconnection (e.g., connected directly to a camera hot shoe, connected viaa wire to a camera hot shoe, connected via a wire to a synchronizationconnector of the camera), initiating light emission of a lighting devicebuilt into the camera, wirelessly initiating light emission of a remotelighting device, and any combinations thereof. In one example, theprocess of initiating the emission of light from a lighting deviceincludes a determination that light emission should be initiated at agiven time as set forth in various embodiments and implementationsherein, generation of a light emission initiation signal, communicationof the initiation signal to the lighting device, and the actualinitiation of light emission by the lighting device.

A delay may exist between the generation of a light emission initiationsignal and the initiation of light emission by a lighting device.Examples of such delay include, but are not limited to, delay due toelectronic circuitry between a generator of a light emission initiationsignal and a light generating element of lighting device, delay due towireless transmission of a light emission initiation signal, and anycombinations thereof. Additionally, upon light emission initiation theremay be additional delay before light is emitted from the device. Such adelay may be due to charging time of a light generating element of thelighting device.

FIG. 5 illustrates one example of timing plots associated with anexemplary synchronization where light emission is initiated after afirst shutter blade begins to allow light to pass to an imaging sensorand before the first shutter blade stops movement. Plot 505 shows themovement of a mirror of a camera from an initial closed position(represented by the initial horizontal line) to a position (representedby the second horizontal portion of the plot) that allows light to passto a shutter mechanism of the camera. Plot 510 shows the movement of anedge of a first shutter blade from an initial position (represented bythe initial horizontal portion of the plot) that blocks light from animaging sensor of the camera to a second stopped position (representedby the second horizontal portion of the plot) that allows light to passthe first shutter blade to the imaging sensor. A diagonal portionconnecting the two horizontal portions represent the movement of thefirst shutter blade from a position fully obstructing light through atime where the imaging sensor is partially blocked by the first shutterblade to a time where the first shutter blade is no longer obstructinglight to the imaging sensor. Initiation of the movement of a firstshutter blade may occur in a variety of ways. In one example, a firstshutter blade occurs as a result of a magnet that holds the shutterblade in place being released. In such an example, a magnet may bereleased by a magnet release signal. Plot 515 shows the movement of anedge of a second shutter blade from an initial position (represented bythe initial horizontal portion of the plot) to a second stopped position(represented by the second horizontal portion of the plot) at which thesecond shutter blade fully blocks light from the lens to the imagingsensor. A diagonal portion of the plot connecting the two horizontalportions represents the movement of the second shutter blade from aposition that does not obstruct light to the sensor through a time wherethe partially obstructs light to the sensor to a time of fully blockinglight to the sensor. Dashed line 520 marks the time at which the edge ofthe first shutter blade clears the imaging sensor such that it no longerblocks light to the imaging sensor. This time occurs prior to the firstshutter blade stopping movement. Dashed line 525 marks the time at whichthe leading edge of the second shutter blade starts to obstruct lightfrom passing to the imaging sensor. This time occurs at a point afterthe second shutter blade has begun movement. The time 530 between time520 and 525 is the time that the imaging sensor is fully unobstructed bythe shutter blades. Plot 535 shows an optional voltage change plotassociated with time period 530. Plot 540 shows a voltage change plot ofa conventional X-Sync signal of the camera that begins with a voltagechange at the time of the first shutter blade stopping movement and endswith a voltage change at the time of the second shutter blade stoppingmovement.

Plot 545 shows a light emission intensity profile of a lighting device.Dashed line 550 marks the intensity level above which the light emissionof the lighting device is detectable by the imaging sensor over ambientlighting. Initial critical point 555 is the point on the light emissionprofile at which the light emission is first detectable by the imagingsensor above the ambient light. Terminal critical point 560 is the pointon the light emission profile at which the light emission is lastdetectable by the imaging sensor above the ambient light. The hashedarea under the light emission curve represents the light emission thatis detectable by the imaging sensor. Light emission is initiated afterthe first shutter blade begins to allow light to pass to the imagingsensor and before the first shutter blade stops movement.

Several possible benefits may arise from initiation of light emissionafter a first shutter blade begins to allow light to pass to the sensorbut before the first shutter blade stops movement. In one exemplaryaspect, selection of the time of light emission initiation may allow thelight emission intensity during the time that the imaging sensor isexposed to light from the camera lens to be balanced across the timefrom the first shutter blade beginning to expose the imaging sensor tothe second shutter blade fully blocking the imaging sensor. In anotherexemplary aspect, light emission may be initiated such that darkenedportions of a resulting image are minimized. In another exemplaryaspect, light emission during shutter blade travel across the imagingsensor may be minimized (e.g., eliminated). In yet another exemplaryaspect, no light emission energy may be wasted prior to the imagingsensor being exposed to the light.

In the example of FIG. 5, the early initiation of light emission is suchthat initial critical point 555 occurs soon enough after time 520 thatterminal critical point 560 occurs prior to time 525. The entire portionof the light emission that is detectable over ambient light occursduring time period 530. No detectable light over ambient light occurswhile either the first shutter blade or the second shutter blade ispartially obstructing light to the imaging sensor.

Initiation of light emission synchronized to image acquisition such thatthe light emission is initiated after a first shutter blade begins toallow light to pass to the imaging sensor and before the first shutterblade stops movement may be useful in any of a variety of imageacquisition environments. Examples of such environments include, but arenot limited to, a camera having a built-in flash, a camera having abuilt-in wireless functionality with one or more remote lightingdevices, a camera having an external wireless functionality with one ormore remote lighting devices, and any combinations thereof. Many directand indirect wiring implementations are known for connecting via wiredelectrical connection a camera and a lighting device. Examples ofwireless functionalities for wirelessly connecting a camera to a remotelighting device include, but are not limited to, an optical wirelessfunctionality (e.g., infrared), a radio frequency wirelessfunctionality, and any combinations thereof.

Various wireless implementations of synchronizing the initiation oflight emission are described below. In one exemplary aspect, wirelesssynchronization of a remote lighting device with a camera includes theuse of a wireless communication device having a transmitter (andpossibly a receiver) associated with the camera side and a wirelesscommunication device having a receiver (and possibly a transmitter)associated with the lighting device side. Example associations of awireless communication device include, but are not limited to, awireless communication functionality at least partially internal to acamera; a wireless communication functionality externally connected tothe internal circuitry of a camera (e.g., via a hot shoe connector), awireless communication functionality at least partially internal to alighting device; a wireless communication functionality externallyconnected to the internal circuitry of a lighting device (e.g., via ahot shoe connector), and any combinations thereof. Examples of suchassociations are described in detail below (e.g., with respect to FIGS.33 to 36. A wireless communication functionality may include circuitryand/or machine executable instructions of an early synchronizer system,such as early synchronizer system 3700 of FIG. 37 for imitating emissionof light by a photographic lighting device at a time with respect toimage acquisition as described by any of the aspects of embodiments andimplementations herein.

A light emission initiation signal may be wirelessly transmitted as atransmission signal from a camera side transmitter to a lighting devicereceiver. Exemplary implementations of wireless transmission signals aredescribed below (e.g., with respect to FIGS. 16 to 18). A light emissioninitiation signal may include instructions for initiating light emissionat the desired time as described herein. Calibration of the timing ofthe initiation may impact the information in the instructions. A timingdelay factor can be utilized in the instructions for setting the time oflight emission initiation. A timing delay factor may be based on thetime between a predictor event and/or signal and the desired time oflight emission initiation. Example relations that may impact a timingdelay factor include, but are not limited to, a relationship to a timeof a first shutter blade clearing the imaging sensor such that it nolonger obstructs light to the sensor, a relationship to a time of afirst shutter blade stopping movement, a relationship to a time of aninitial critical point of a flash profile of a lighting device, arelationship to a time of a terminal critical point of a flash profileof a lighting device, a time of a predictor event and/or signal, a timeof the starting of movement of a second shutter blade, and anycombinations thereof. Values for any of these times may be stored inmemory of an early synchronizer system for one or more cameras andimaging conditions (e.g., shutter speed) and used to generate the timingdelay factor. In one example, a delay factor is an absolute time value(e.g., in relation to a prior event and/or signal, such as a predictorevent and/or signal). In such an example, an early synchronizer systemat the camera side or the lighting device side may generate the absolutetime value for initiating light emission based on information from thecamera and communicate a light emission initiation signal to thelighting device. In another example, a delay factor is an offset valuefrom one or more other events (e.g., the reception of the light emissioninitiation signal transmission). In one such example, an earlysynchronizer system at the lighting device side includes a delay factorhaving an offset value. When the transmission signal is received, theearly synchronizer system calculates a time for initiation of lightemission from the time of reception using the offset value. In anothersuch example, the transmission signal includes information having thedelay factor with an offset value. When the transmission signal isreceived, the early synchronizer system calculates a time for initiationof light emission from the time of reception using the offset value.

In one implementation, a timing delay factor may be modified by theapplication of an adjustment delay. An adjustment delay may allow a userto modify timing of light emission initiation. An early synchronizationsystem may include an interface for inputting an adjustment value thatcan be applied to one or more timing delay factors utilized insynchronizing one or more lighting devices. Example interfaces and inputdevices are described below with respect to exemplary systems of FIGS.33 to 38.

Multiple light emission initiation signal transmissions may betransmitted at the same time. In one example, remote lighting devicesmay be grouped into two or more zones (e.g., with different settings,different desired emission initiation times, and/or having differentcapabilities for processing delays). In one such example, one or morelighting devices may be grouped together because they are not capable ofimplementing a timing delay factor (e.g., the lighting device and/orassociate wireless communication device do not have an associated earlysynchronization device as described herein). Another grouping may becapable of delay. A camera side wireless communication device having anearly synchronization functionality associated therewith may generatetwo transmission signals, one having a timing delay factor andtransmitted on a first frequency prior to X-synch and another configuredto provide a direct initiation of a light emission procedure without adelay factor being transmitted on a second frequency for reception atthe desired time of light emission initiation.

FIG. 6 illustrates one example of a timeline showing initiation of aflash emission during a time 605 after a first shutter blade of a camerabegins to allow light to pass to an imaging sensor and before the timethat the first shutter blade stops movement. FIG. 6 is not intended toconvey a specific relationship in time duration. As discussed above alight emission initiation signal may be generated to bring about theinitiation of a flash emission during time 605. The time between thegeneration of the light emission initiation signal and light emissioninitiation may be impacted by any of a variety of factors. Examples ofsuch factors include, but are not limited to, a time required totransmit a light emission initiation signal via electronic wiring andcircuitry to a light emission element of a lighting device, a timerequired to wirelessly transmit a light emission initiation signal to awireless device associated with a remote lighting device, charging timeof a light emission element of a lighting device, and any combinationsthereof. Consideration of one or more such factors may be taken in thedetermination of timing for generation of a light emission initiationsignal and/or the timing of wireless transmission of such a signal. Inone example, a light emission initiation signal may be wirelesslytransmitted in advance of a desired light emission initiation time. Inone such example, a wirelessly transmitted initiation signal may includea time coding (e.g., data including a time delay) that the receivingremote device (e.g., the receiving wireless device) may interpret todetermine the desired time of light emission initiation.

In one embodiment, a signal and/or an event of a camera may be utilizedto predict the time for light emission initiation. In one such example,a camera that is not configured for early synchronization may bemodified (e.g., via an internal modification and/or an externally addedcomponent, such as an external wireless device) to synchronize imageacquisition with light emission initiation that occurs after a firstshutter blade of the camera starts to allow light to pass to an imagingsensor of the camera and before the first shutter blade stops movement.FIG. 7 illustrates one example of a timeline showing detection of apredictor signal and/or predictor event for initiation of a flashemission after a first shutter blade of a camera begins to allow lightto pass to an imaging sensor and before the time that the first shutterblade stops movement. FIG. 7 shows a time of detecting a predictorsignal and/or event of a camera. It should be noted that detecting iscontemplated to include receiving a predictor signal and/or event. Flashinitiation occurs after first shutter blade begins to allow light topass to the sensor and before the time that the first shutter bladestops movement. In one example, a time 705 between a predictor signaland/or event and a first shutter blade stopping movement may be anapproximately fixed time from which a time of flash initiation can bedetermined to maximize desired image quality. The fixed nature of time705 may depend on any one or more of a variety of factors. Such factorsinclude, but are not limited to, a camera model, the nature of thedetected signal and/or event, a camera setting, and any combinationsthereof.

Example signals and events that may be utilized to predict timing forlight emission initiation include, but are not limited to, a flash powerlevel set command, a flash mode set command, a change in voltage on aclock signal of a camera, a magnet release associated with the start ofa first shutter blade movement, a magnet release signal associated withthe start of a first shutter blade movement, one or more data signalsgenerated by a camera, an FP-sync signal of a camera, and anycombinations thereof. In one example, a magnet release signal isutilized as a predictor signal. A magnet release signal may occur viaone or more circuit elements of a camera at or about the time that themirror has moved to an open position. A time period may occur between amagnet release signal (and/or actual magnet release) and the time of afirst shutter blade starting to move. This may be due to magneticdecharging effects. An FP-sync mode of a camera is one that generates aflash emission similar to that discussed above with respect to FIG. 3 inwhich light emission is initiated prior to a first shutter bladebeginning movement such that a pseudo-constant light emission occursfrom before the first shutter blade allowing light to pass to the sensorto after the second shutter blade fully blocks the sensor. A cameracapable of an FP-sync mode may generate an FP-sync signal to initiatelight emission prior to first shutter blade movement. In one example,the time between an FP-sync signal and a first shutter blade stoppingmovement is determined and reliably used to determine the time fordesired light emission after a first shutter blade has begun to allowlight to pass to the sensor. In yet another example, a change in voltageof a clock signal occurring prior to X-sync is utilized as a predictorsignal. In one such example, the time from the initiation of the voltagedrop on the clock signal to the time of desired light emissioninitiation can be reliably utilized in synchronizing light emission. Instill another example, a data signal of a camera is utilized as apredictor signal. In one such example, a data signal is a power setcommand on a data line of the camera occurring prior to X-sync isutilize reliably to initiate flash emission at the desired time.

Calibration of light emission initiation time may occur. In one example,calibration of light emission initiation timing may occur prior to animage acquisition session (e.g., via data determined duringmanufacturing of a synchronizing device utilized to add earlysynchronization capability to a camera, via data determined duringmodification of a camera). In another example, calibration of lightemission initiation timing may occur at or near the time of an imageacquisition session.

In one implementation of calibration, proper timing of a light emissioninitiation timing may be determined with a qualitative review of imagequality produced with light emission initiated at one or more timesduring period 705.

In another exemplary implementation, a camera can be tested to determinetime period 705 for that camera and a given predictor signal and/orevent. In one example, an image acquisition procedure is conducted(e.g., camera trigger is depressed and an image is acquired). Apredictor signal and/or predictor event is detected (e.g., a magnetrelease signal is detected). The timing of a first shutter bladestopping movement is detected (e.g., detecting X-sync signal). The timebetween the time of the predictor signal and/or predictor event and thetime of the first shutter blade stopping movement is determined. Thattime (e.g., time 705) may be stored for later use (e.g., in a memoryelement of the camera, in a memory element of a flash synchronizerdevice, such as a wireless device added to a hot shoe connector of acamera or internally to a camera). Time 705 may be determined formultiple cameras and stored in memory. Data representing a time 705 maybe associated with data representing a corresponding camera model. Somecameras produce a data signal that identifies the camera model (e.g.,via a hot shoe connector of the camera). That data signal can bedetected and used to correlate data representing time 705 to datarepresenting a camera model.

In another example, an image acquisition procedure is conducted with acamera at a shutter speed for which the camera generates an X-syncsignal at the time that a first shutter blade of the camera stopsmovement. Data related to the time of the X-sync signal is detected andrecorded (e.g., in a memory). Another image acquisition procedure isconducted with the camera at a shutter speed for which the cameragenerates an FP-sync signal (e.g., the camera does not generate anX-sync signal). The timing of the FP-sync signal is determined andrecorded (e.g., in a memory). The time between the FP-sync signal andthe X-sync signal is determined and recorded (e.g., in a memory) as time705 for that camera.

The determination of time 705 may be made at any time. In one example,time 705 is determined at the time of manufacture of a synchronizingdevice (e.g., an external device, a device for internal connection in acamera). In another example, time 705 is determined at a time ofmodification of a camera to perform early synchronization according toany one or more of the implementations or embodiments disclosed herein.In another example, time 705 is determined by a camera user at or aboutthe time of calibration of the early synchronization functionality foruse at a particular shutter speed to produce a desired image qualityupon light emission and image acquisition.

Referring again to FIG. 7, time period 710 represents the time from thepredictor event and/or signal to the desired light emission initiation.Time period 715 represents the time between desired light emissioninitiation and the time of a first shutter blade stopping movement. Timeperiod 710 and 715 are shown for exemplary purposes only and the actualscale of FIG. 7 is not meant to imply a relative quantitative timeduration between time period 710 and 715. Time period 710 and timeperiod 715 may divide time period 705 into any two time durations (e.g.,as will have light emission initiation occur to produce desired effectsin an acquired image). Time periods 705, 710, and/or 715 may be utilizedto calibrate a light emission initiation for desired image quality.

In another exemplary implementation, a camera user may determine adesired value for time period 715 such that light emission initiationoccurs at a desired time (e.g., to produce a desired effect on anacquired image). The time period 715 may then be used in conjunctionwith stored information about time period 705 (and possibly known timedelays between light emission signal generation and actual lightemission initiation) to initiate light emission at the desired time. Inone example, an early synchronizing functionality may detect data fromthe camera about the camera's model and use that information tocorrelate to stored values for time period 705. In another example, auser may input camera model data to the early synchronizingfunctionality via a user input. In one such implementation, a userinitiates an image acquisition procedure to acquire an image with theshutter speed of the camera at a particular setting and light emissioninitiation at a starting value of time period 715. In one example, thefastest desired shutter speed can be used as an initial calibration(e.g., 1/500^(th) of a second). In another example, a slower thanmaximum desired shutter speed can be used as an initial calibration. Theuser empirically evaluates the desired effect of the time period 715calibration on image quality. The user may then decrease time period 715(e.g., via a user input on the synchronization device, a user input onthe camera, and/or a user calibration utility that may be used toprogram a synchronization functionality), for example if the resultantimage has darkened areas due to excessive light emission during bladetravel across the sensor. The user may also increase time period 715(e.g., via user input), for example if the resultant image has nodarkened areas due to excessive light emission during blade travelacross the sensor. The process of reviewing pictures and adjusting timeperiod 715 can be repeated until the desired calibration is acquired.The desired time period 715 calibration can be stored in memory. Thedata for time period 715 may be associated with data representing thecorresponding shutter speed and/or data representing the correspondinglighting device utilized.

In another example, the time period adjusted during calibration could betime period 705. In yet another example, calibration values for any oneor more of time periods 705, 710, 715 may be in units that are not timebased units (e.g., absolute numerical units, such as from a minimum tomaximum offset from the time of the first shutter blade stoppingmovement).

As discussed above, the timing of light emission initiation can bemaximized such that darkened areas of a resultant image are minimized ata given shutter speed (e.g., shutter speeds for which synchronization atconventional sync signals is not possible). Darkened regions are visiblydarker regions than other areas of the image. In one such example,calibration can be utilized to have the timing of light emissioninitiation such that no darkened regions of the image result. In anotherexample, calibration can be utilized to have the timing of lightemission initiation such that only minor regions of the edge of an imagehave darkening. Image acquisition in such an example can occur such thatthese minor regions do not interfere with the subject of the image(e.g., the sides can be cropped). In yet another example, calibrationcan occur such that light emission initiation occurs such that theintegral of light emission is balanced across the time period betweenfirst blade beginning to expose the sensor and the second blade fullyblocking the sensor. In such an example, a non-continuous lightintensity light source may be utilized to achieve visibly even lightingacross the sensor. In still another example, technical clipping of lightemission (i.e., an initial critical point occurs prior to a firstshutter blade no longer blocking the sensor, a terminal critical pointoccurring after the second shutter blade begins to obscure the sensorfrom light) may occur with visibly little impact on the resultant imagequality (e.g., no significantly visibly detectible image darkenedregions on the resultant image).

Table 1 includes example data for exemplary calibrations conducted onvarious Canon cameras (listed in first column) using different lightdevices (e.g., Speedlight, Dynalite strobe, Profoto Acute2 2400, andElincrhom Style 300RX). To determine when the desired time according tothe table to initiate light emission for each camera with each flash atthe stated shutter speed, an additional calibration value is utilized:the time from the occurrence of the predictor signal/event to X-sync.The values in Table 1 are subtracted from that value to determine thetime from the predictor signal and/or event to the time of lightemission initiation. This determined time can be used with other values(e.g., knowledge of time requirements for wireless transmission of ainitiation signal, time from the predictor signal and/or event to thestart of transmission of the initiation signal transmission, knowledgeof the length of the pulse of the wireless transmission) to calculate atime delay value to include with a transmission signal communicated tothe lighting device prior to the desired time or light emissioninitiation. For example, a desirable image quality was determined usinga Canon 1D mk II with a Speedlight at 1/500^(th) of a second shutterspeed by using a value for time period 1115 of 320 microseconds (us). Inanother example, it is noted that the blade travel time for the Canon 5DMark II is relatively slow. This allows a calibration value of 1400microseconds to still have the initiation of light emission occur afterthe first shutter blade begins to expose the sensor to light.

TABLE 1 Example Calibration Adjustments for Example Cameras and Flashesat Certain Shutter Speeds Flash Model Elinchrom Style Canon CameraSpeedlight Dynalite 1000wi Profoto Acute2 2400 300RX 1D mk II −320 us @500th −400 us @ 500th −600 us @ 500th −270 us @ 500th 1D mk III −190 us@ 500th −400 us @ 500th −500 us @ 500th −160 us @ 500th 1Ds mk II 1Ds mkIII 20D 30D −270 us @ 400th −350 us @ 400th −550 us @ 400th −270 us @400th 40D −170 us @ 400th −450 us @ 400th −750 us @ 400th −330 us @400th 50D −170 us @ 400th −450 us @ 400th −750 us @ 400th −330 us @400th Rebel Xsi −400 us @ 320th −620 us @ 320th −700 us @ 320th −400 us@ 400th 5D 5D mk II −300 us @ 250th −1000 us @ 250th  −1400 us @ 320th −650 us @ 320th

In another exemplary implementation, dynamic adjustment of calibrationvalues (e.g., time period 715 values) can be implemented based on astored value at a given shutter speed. For example, if a value for timeperiod 715 is 300 microseconds at 1/500^(th) of a second shutter speedfor a given camera and light combination, the values for time period 715at other shutter speeds can be dynamically assigned (e.g., via aprocessing element and/or other circuitry of a camera and/or asynchronizing device). In one example, the total calibration value(e.g., the time value of time period 715) can be divided by the numberof partial f-stops between the shutter speed for the known calibrationvalue and the shutter speed known to work at X-sync (typically the timethat the first shutter blade stops movement). For the above example of300 microseconds at 1/500^(th) of a second. It may be known that ashutter speed of 1/250^(th) of a second is the fastest X-sync shutterspeed supported by a camera. There may be three partial f-stops between1/500^(th) and 1/250^(th) of a second (e.g., 1/500^(th), 1/400^(th),1/320^(th), 1/250^(th)). A dynamic assignment of a calibration value of200 microseconds can be assigned to shutter speeds of 1/400^(th), 100microseconds can be assigned to shutter speeds of 1/320^(th) of asecond, and zero microseconds can be assigned to 1/250^(th) of a second.

FIG. 8 illustrates timing data for a camera and flash combinationworking at 1/200^(th), 1/250^(th), 1/320^(th), and 1/400^(th) of asecond shutter speeds. FIG. 8 shows a flash pulse profile for lightemission for each shutter speed initiated at differing calibrationvalues of time period 715. In each case, light emission was initiatedafter the first shutter blade began to allow light to pass to the sensorbut before the x-sync signal. The earlier initiation times for thefaster shutter speeds eliminated clipping in the resultant images.

FIG. 9 illustrates another embodiment of a method of earlysynchronization. At step 905 a photographic lighting device having alight emission profile having an initial critical point and a terminalcritical point is provided. Initial and terminal critical points arediscussed above. At step 910 a light emission is initiated from thephotographic lighting device prior to a first shutter blade of a cameraassociated with the photographic lighting device stopping movement. Theinitiation of light emission is such that the initial critical pointoccurs at a point in time after about 1 millisecond before the firstshutter blade moves to a point where the first shutter blade no longerobstructs light to the sensor.

In one example, the initial critical point occurs after 500 microsecondsbefore the first shutter blade moves to a point where the first shutterblade no longer obstructs light to the sensor. In another example, theinitial critical point occurs after 250 microseconds before the firstshutter blade moves to a point where the first shutter blade no longerobstructs light to the sensor. In yet another example, the initialcritical point occurs at approximately the same time as a time when thefirst shutter blade moves to a point where the first shutter blade nolonger obstructs light to the sensor. In still another example, theinitial critical point occurs after the time that the first shutterblade moves to a point where the first shutter blade no longer obstructslight to the sensor. In yet still another example, the initial criticalpoint occurs before the first shutter blade stops movement. In a furtherexample, the terminal critical point occurs before 500 microsecondsafter the second shutter blade moves to a point where the second shutterblade starts to obstruct light from passing to the sensor. In a still afurther example, the terminal critical point occurs before 250microseconds after the second shutter blade moves to a point where thesecond shutter blade starts to obstruct light from passing to thesensor. In yet a further example, the terminal critical point occurs atabout the time that the second shutter blade moves to a point where thesecond shutter blade starts to obstruct light from passing to thesensor. In still yet a further example, the terminal critical pointoccurs before the time that the second shutter blade moves to a pointwhere the second shutter blade starts to obstruct light from passing tothe sensor. It is contemplated that various implementations existcombining any one or more of the examples of this paragraph to providean initial time limit for the occurrence of the initial critical point,a terminal time limit for the occurrence of the terminal critical point,and/or a terminal time limit for the occurrence of the initial criticalpoint. For example, in one implementation, the initial critical pointoccurs after the time that the first shutter blade moves to a pointwhere the first shutter blade no longer obstructs light to the sensorand the terminal critical point occurs before the time that the secondshutter blade moves to a point where the second shutter blade starts toobstruct light from passing to the sensor.

FIG. 10 illustrates a timing plot showing the time 1005 between flashinitiation and the initial critical point. This time can be utilized inthe calibration processes described above to offset the time of thelight emission initiation to have the initial critical point occur at adesired time. In one example, time 1005 is measured for a flash device.The measured time value may be stored in a memory for use in calibrationand operation of a early synchronization system (e.g., system 1300). Inone example, empirical observation of a resultant image acquisition withvarying calibration offset values based on a time 1005 may indicate anoptimal location of the initial critical point with respect to the timeat which the edge of the first shutter blade fully clears fromobstructing the sensor.

FIG. 11 illustrates a timing plot showing the time 1105 between desiredflash initiation and the initial critical point. Time 1110 is the timebetween a detected predictor signal and desired flash initiation.

FIG. 12 illustrates a timing plot showing the time 1205 between desiredflash initiation and the initial critical point. Time 1215 is the timebetween the time of generation of a flash initiation signal and the timeof desired flash initiation. As discussed above time 1215 may beinfluenced, for example, by circuitry transmission time and/or wirelesstransmission time.

FIG. 13 illustrates a timing plot showing the time 1305 between desiredflash initiation and the initial critical point. Time 1310 is the timebetween a detected predictor signal and desired flash initiation. Time1315 is the time between the time of generation of a flash initiationsignal and the time of desired flash initiation.

In one exemplary implementation, utilization of time period 1005 andcalibration information discussed above (e.g., time between predictorsignal/event and X-synch, time of calibration offset value, and time tothe time of desired light emission initiation from predictorsignal/event), the timing of the initial critical point can bepositioned at a desired time after 1 ms before first shutter bladeclearance of the sensor.

FIG. 14 illustrates another implementation of a method of synchronizingone or more lighting devices to an image acquisition using a predictorsignal and/or event. At step 1405, a predictor signal and/or event isdetected. At step 1410, a time from the time predictor signal and/orevent to the desired time of the initial critical point is correlated.In one example, correlation of a time of an initial critical pointincludes determining the time from the predictor signal and/or eventoccurrence to the occurrence of the initial critical point, andsubtracting out a known value for the time from the initiation of lightemission for the lighting device and the time at which the lightingdevice creates light at the initial critical point. In another example,correlation of the time of the initial critical point includesreferencing a table having time values (e.g., including time delayvalues) for a lighting device that provides the time from the occurrenceof the predictor signal and/or event to the time of desired lightemission initiation. Other ways of correlating the appropriate time oflight emission initiation will be apparent to those of ordinary skillfrom the disclosure herein. At step 1415, a light emission is initiatedsuch that the initial critical point is at a desired time after 1millisecond before the first shutter blade clears the imaging sensor. Atstep 1420, an image is acquired using the one or more lighting devices.

FIG. 15 illustrates yet another implementation of a method ofsynchronizing a given type of image exposure light emission of one ormore lighting devices to an image acquisition. At step 1505, a camerapredictor event and/or signal is identified that is not an event orsignal intended for instructing the initiation of X-sync and occursprior to the time of X-sync. In one example, the predictor event and/orsignal occurs prior to a first shutter blade of the camera moving to apoint that allows light to pass to an imaging portion of the sensor. Atstep 1510, based upon the occurrence of the predictor event and/orsignal, an instruction for initiating the light emission is communicatedto the photographic lighting device. At step 1515, light emission isinitiated. In one example, light emission is initiated after a firstshutter blade begins to expose an imaging portion of an imagingacquisition sensor of a camera and before X-sync associated withstopping of the first shutter blade movement. In another example, lightemission is initiated such that an initial critical point of a flashprofile of a lighting device occurs at a point in time after about 1millisecond before the first shutter blade moves to a position that nolonger obstructs light to the imaging portion of the sensor.

As discussed above, various camera predictor events and signals areavailable for use in synchronizing. In one example, a camera predictorevent and/or signal is a serial data communication of the camera. In onesuch example, a serial data communication is a power set command. Inanother example, a serial data communication is a mode set command. In afurther example, a camera predictor event and/or signal is a drop in avoltage of a clock signal of the camera. In yet another example, acamera predictor event and/or signal is the initiation of a shuttermagnet release signal. In still another example, a camera predictorevent and/or signal is the initiation of an FP-sync signal and theinitiating light emission does not include an FP-type flash emission.

Communicating an instruction for initiating light emission to aphotographic lighting device can occur in a variety of ways. Asdiscussed above, light emission initiation can occur in manyenvironments. In one example, such communicating includes delivering theinstruction internal to the camera to an internal lighting device. Thismay be done by a wired electrical connection. In another example, suchcommunicating includes delivering the instruction via a hot shoeconnector of the camera to the photographic lighting device, thephotographic lighting device being positioned in the hot shoe connector.In still another example, such communicating includes wirelesslytransmitting the instruction to the photographic lighting device.Various wireless transmission functionalities and processes arediscussed herein with respect to other implementations and, asappropriate, are useful here. In one such example of wirelesstransmitting, a wireless communication device is connected to the camera(e.g., via a hot shoe connector, via a USB connector, via a proprietaryconnector, etc.) and provides a wireless communication functionality tothe camera for wirelessly transmitting an instruction to a remotelighting device. In another such example, a wireless communicationfunctionality is internal to the camera and is utilized for wirelesslytransmitting an instruction to a remote lighting device.

Wireless communication of the instruction can occur at a variety oftimes. In one example, the instruction is wirelessly transmitted priorto the first shutter blade moving to a position that no longer obstructslight to the imaging portion of the sensor. In another example, theinstruction is received by a wireless communications receiver associatedwith the photographic lighting device prior to the first shutter blademoving to a position that no longer obstructs light to the imagingportion of the sensor. In yet another example, the instruction iswirelessly transmitted prior to the occurrence of the normal flashinitiation event or signal. In still another example, the instruction isreceived by a wireless communications receiver associated with thephotographic lighting device prior to the occurrence of the normal flashinitiation event or signal.

An instruction for initiating light emission includes information for alighting device to determine the proper time for actual light emission.As discussed above, various factors may influence the timing of actuallight emission with respect to the transmission and receipt of aninstruction for initiating the emission. The light emission may occur ata time that is delayed from the receipt of the instruction by a lightingdevice (e.g., by a wireless receiving device associated with thelighting device). In one example, the instruction includes aprecalculated time for initiating light emission. In another example,the instruction includes a delay factor.

FIG. 16 illustrates an exemplary implementation of a method ofsynchronizing one or more lighting devices to an image acquisition of acamera. The method is shown with the aid of various plots 1600 over timefrom the left of the plots to the right. The method utilizes a predictorsignal 1605 that is a serial data transmission of a serial data outputof a camera represented in voltage plot 1610. In one example, predictorsignal 1605 is a series of data communications of a power set command.In one such example, the power set command occurs prior to the start ofmovement of the first shutter blade. Plot 1615 represents the physicalmovement of a mirror of a camera from an initial closed position(represented by the initial lower horizontal line) to a position(represented by the second upper horizontal portion of the plot) thatallows light to pass to a shutter mechanism of the camera. Plot 1620shows the movement of an edge of a first shutter blade from an initialposition (represented by the initial horizontal portion of the plot)that blocks light from an imaging sensor of the camera to a secondstopped position (represented by the second horizontal portion of theplot). In the stopped position, the first shutter blade does not blocklight from passing to the imaging sensor. A diagonal portion connectingthe two horizontal portions represents the movement of the first shutterblade from a position fully obstructing light through a time where theimaging sensor is partially blocked by the first shutter blade to a timewhere the first shutter blade is no longer obstructing light to theimaging sensor. Initiation of the movement of a first shutter blade mayoccur in a variety of ways. In one example, a first shutter blade occursas a result of a magnet that holds the shutter blade in place beingreleased. In such an example, a magnet may be released by a magnetrelease signal. Plot 1625 shows the movement of an edge of a secondshutter blade from an initial open position (represented by the initialhorizontal portion of the plot) to a second stopped position(represented by the second horizontal portion of the plot) at which thesecond shutter blade fully blocks light from the lens to the imagingsensor. A diagonal portion of the plot connecting the two horizontalportions represents the movement of the second shutter blade from aposition that does not obstruct light to the sensor through a time wherethe shutter blade partially obstructs light to the sensor to a time offully blocking light to the sensor. Dashed line 1630 marks the time atwhich the edge of the first shutter blade clears the imaging sensor suchthat it no longer blocks light to the imaging sensor. In this example,this time occurs prior to the first shutter blade stopping movement.Dashed line 1635 marks the time at which the leading edge of the secondshutter blade starts to obstruct light from passing to the imagingsensor. In this example, this time occurs at a point after the secondshutter blade has begun movement. The time 1640 between dashed lines1630 and 1635 is the time that the imaging sensor is fully unobstructedby the shutter blades. Plot 1645 shows an optional voltage change plotassociated with time period 1640. Plot 1650 shows a voltage change plotof a conventional X-Sync signal of the camera that begins with a voltagechange at about the time of the first shutter blade stopping movementand ends with a voltage change at the time of the second shutter bladestopping movement.

Plot 1655 represents a wireless transmission signal used to communicatesynchronization information from a camera to one or more photographiclighting devices according to any one of the implementations forinitiating light emission described herein. Plot 1655 includesrepresentations for a first synchronization transmission 1660, and asecond synchronization transmission 1662, a data transmission 1664.First synchronization transmission 1660 is a transmission includinginstructions for synchronizing the initiation of light emission by aphotographic lighting device according to any one or more of theembodiments and implementations of timing of emission initiationdiscussed herein. Second synchronization transmission 1662 is anoptional transmission. In this example, second synchronizationtransmission 1662 is for receipt by one or more lighting devices notassociated with a functionality for early synchronization with timedelay factors. Second synchronization transmission 1662 provides such adevice with a wireless light emission initiation direct signal such thatthe time of initiation is at about the time of receipt of the wirelesstransmission (e.g., at the time of X-sync or another predeterminedtime). In one example, transmissions 1660 and 1662 are configured tohave light emission initiation by their corresponding lighting devicesoccur at the same time. In another example, transmissions 1660 and 1662are configured to have light emission initiation at different times.Data transmission 1664 is also an optional transmission. An earlytransmitted data transmission can provide information about the imageacquisition (e.g., other than timing information), information about thecamera, and any combinations thereof to a remote lighting device. Inthis example, data transmission 1664 transmits information regardingpower settings obtained from the power set command 1605.

Plot 1670 shows a light emission intensity profile of a lighting device.Dashed line 1672 marks the intensity level above which the lightemission of the lighting device is detectable by the imaging sensor overambient lighting. Initial critical point 1674 is the point on the lightemission profile at which the light emission is first detectable by theimaging sensor above the ambient light. Terminal critical point 1676 isthe point on the light emission profile at which the light emission islast detectable by the imaging sensor above the ambient light. Thehashed area under the light emission curve represents the light emissionthat is detectable by the imaging sensor. Light emission is initiatedafter the first shutter blade begins to allow light to pass to theimaging sensor and before the first shutter blade stops movement.

In this implementation, the predictor signal 1605 is detected. In oneexample, the occurrence is measured from the last data bit at the timerepresented by the dotted line 1680. Based on the occurrence ofpredictor signal 1605, first synchronization transmission 1660 iscommunicated to a lighting device. First synchronization transmission1660 includes instructions for initiating light emission of the lightingdevice such that light emission is initiated as shown in plot 1670. Inthis example, light emission is initiated prior to X-sync and after thefirst shutter blade begins to expose the sensor. The initial criticalpoint 1674 and terminal critical point 1676 each occur within the timewindow 1640. As discussed above, light emission can be initiated suchthat critical point 1674 occurs at any of a variety of times withrespect to an X-sync time and/or the time represented by line 1630. Itis contemplated that the examples discussed above could apply to thetiming of initial critical point 1674.

As is shown with respect to FIG. 16, first synchronization transmissioninitiates at a time 1685 after the occurrence of predictor signal 1605and at a time 1690 before the first shutter blade clears the sensor(i.e., the time shown by line 1630). The instructions for initiatinglight emission included in synchronization transmission 1660 may utilizethe total time between time 1680 and time 1630, the time 1685, the time1690, a time delay factor, known delays due to transmission, knowndelays due to excitation of lighting device, and/or other factors indetermining the time 1685 for transmission after predictor signal 1605and/or in determining a time delay factor included in the instructionsfor when the light emission initiation occurs after receipt of thetransmission 1660. Various calibration procedures were discussed above.Additional calibration procedures are discussed further below (e.g.,with respect to FIGS. 19 and 20).

FIG. 17 illustrates an exemplary implementation of a method ofsynchronizing one or more lighting devices to an image acquisition of acamera. The method is shown with the aid of various plots 1700 over timefrom the left of the plots to the right. The method utilizes an FP-syncsignal as discussed below as a predictor signal. Data signal 1705 is aserial data transmission of a serial data output of a camera representedin voltage plot 1710. Plot 1715 represents the physical movement of amirror of a camera from an initial closed position (represented by theinitial lower horizontal line) to a position (represented by the secondupper horizontal portion of the plot) that allows light to pass to ashutter mechanism of the camera. Plot 1720 shows the movement of an edgeof a first shutter blade from an initial position (represented by theinitial horizontal portion of the plot) that blocks light from animaging sensor of the camera to a second stopped position (representedby the second horizontal portion of the plot). In the stopped position,the first shutter blade does not block light from passing to the imagingsensor. A diagonal portion connecting the two horizontal portionsrepresents the movement of the first shutter blade from a position fullyobstructing light through a time where the imaging sensor is partiallyblocked by the first shutter blade to a time where the first shutterblade is no longer obstructing light to the imaging sensor. Initiationof the movement of a first shutter blade may occur in a variety of ways.In one example, a first shutter blade occurs as a result of a magnetthat holds the shutter blade in place being released. In such anexample, a magnet may be released by a magnet release signal. Plot 1725shows the movement of an edge of a second shutter blade from an initialopen position (represented by the initial horizontal portion of theplot) to a second stopped position (represented by the second horizontalportion of the plot) at which the second shutter blade fully blockslight from the lens to the imaging sensor. A diagonal portion of theplot connecting the two horizontal portions represents the movement ofthe second shutter blade from a position that does not obstruct light tothe sensor through a time where the shutter blade partially obstructslight to the sensor to a time of fully blocking light to the sensor.Dashed line 1730 marks the time at which the edge of the first shutterblade clears the imaging sensor such that it no longer blocks light tothe imaging sensor. In this example, this time occurs prior to the firstshutter blade stopping movement. Dashed line 1735 marks the time atwhich the leading edge of the second shutter blade starts to obstructlight from passing to the imaging sensor. In this example, this timeoccurs at a point after the second shutter blade has begun movement. Thetime 1740 between dashed lines 1730 and 1735 is the time that theimaging sensor is fully unobstructed by the shutter blades. Plot 1745shows an optional voltage change plot associated with time period 1740.Plot 1750 shows a voltage change plot of a conventional X-Sync signal ofthe camera that begins with a voltage change at about the time of thefirst shutter blade stopping movement and ends with a voltage change atthe time of the second shutter blade stopping movement. Plot 1752 showsa voltage change plot of a conventional FP-sync signal of the camerathat begins with a voltage change at a time represented by line 1780that occurs prior to the first shutter blade starting to expose theimaging sensor. In one exemplary aspect of some systems having anFP-sync signal, there is no X-sync signal generated by the camera. Insuch a situation, the timing of X-sync (and timing of light emissioninitiation with respect thereto) can be determined using otherindications, such as determination of the time of stopping of the firstshutter blade movement. Other options will be apparent to those ofordinary skill from the disclosure herein.

Plot 1755 represents a wireless transmission signal used to communicatesynchronization information from a camera to one or more photographiclighting devices according to any one of the implementations forinitiating light emission described herein. Plot 1755 includesrepresentations for a first synchronization transmission 1760, and asecond synchronization transmission 1762, a data transmission 1764.First synchronization transmission 1760 is a transmission includinginstructions for synchronizing the initiation of light emission by aphotographic lighting device according to any one or more of theembodiments and implementations of timing of emission initiationdiscussed herein. Second synchronization transmission 1762 is anoptional transmission. In this example, second synchronizationtransmission 1762 is for receipt by one or more lighting devices notassociated with a functionality for early synchronization with timedelay factors. Second synchronization transmission 1762 provides such adevice with a wireless light emission initiation direct signal such thatthe time of initiation is at about the time of receipt of the wirelesstransmission (e.g., at the time of X-sync or another predeterminedtime). In one example, transmissions 1760 and 1762 are configured tohave light emission initiation by their corresponding lighting devicesoccur at the same time. In another example, transmissions 1760 and 1762are configured to have light emission initiation at different times.Data transmission 1764 is also an optional transmission. An earlytransmitted data transmission can provide information about the imageacquisition (e.g., other than timing information), information about thecamera, and any combinations thereof to a remote lighting device. Inthis example, data transmission 1764 transmits information regardingpower settings obtained from the power set command 1705.

Plot 1770 shows a light emission intensity profile of a lighting device.Dashed line 1772 marks the intensity level above which the lightemission of the lighting device is detectable by the imaging sensor overambient lighting. Initial critical point 1774 is the point on the lightemission profile at which the light emission is first detectable by theimaging sensor above the ambient light. Terminal critical point 1776 isthe point on the light emission profile at which the light emission islast detectable by the imaging sensor above the ambient light. Thehashed area under the light emission curve represents the light emissionthat is detectable by the imaging sensor. Light emission is initiatedafter the first shutter blade begins to allow light to pass to theimaging sensor and before the first shutter blade stops movement.

In this implementation, the data signal 1705 is detected. In thisexample, this signal 1705 is utilized to provide data for datatransmission 1764. The initiation of the FP-sync signal (as indicated bythe voltage drop at time zzz80) is utilized as the predictor signal.Based on the occurrence of predictor signal, first synchronizationtransmission 1760 is communicated to a lighting device. Firstsynchronization transmission 1760 includes instructions for initiatinglight emission of the lighting device such that light emission isinitiated as shown in plot 1770. In this example, light emission isinitiated prior to X-sync and after the first shutter blade begins toexpose the sensor. The initial critical point 1774 and terminal criticalpoint 1776 each occur within the time window 1740. As discussed above,light emission can be initiated such that critical point 1774 occurs atany of a variety of times with respect to an X-sync time and/or the timerepresented by line 1730. It is contemplated that the examples discussedabove could apply to the timing of initial critical point 1774.

As is shown with respect to FIG. 17, first synchronization transmissioninitiates at a time 1785 after the occurrence of the FP-sync predictorsignal and at a time 1790 before the first shutter blade clears thesensor (i.e., the time shown by line 1730). The instructions forinitiating light emission included in synchronization transmission 1760may utilize the total time between time 1780 and time 1730, the time1785, the time 1790, a time delay factor, known delays due totransmission, known delays due to excitation of lighting device, and/orother factors in determining the time 1785 for transmission afterpredictor signal and/or in determining a time delay factor included inthe instructions for when the light emission initiation occurs afterreceipt of the transmission 1760. Various calibration procedures werediscussed above. Additional calibration procedures are discussed furtherbelow (e.g., with respect to FIGS. 19 and 20).

FIG. 18 illustrates an exemplary implementation of a method ofsynchronizing one or more lighting devices to an image acquisition of acamera. The method is shown with the aid of various plots 1800 over timefrom the left of the plots to the right. The method utilizes acombination of an indicator signal 1805 and a predictor signal (e.g., adrop in voltage of a clock line of the camera as represent by plotzzz08. Data signal 1805 is a serial data transmission of a serial dataoutput of a camera represented in voltage plot 1810. Predictor signal1812 initiates at a time represented by dotted line 1880 that occursprior to the first shutter blade clearing the sensor at time 1830. Plot1815 represents the physical movement of a mirror of a camera from aninitial closed position (represented by the initial lower horizontalline) to a position (represented by the second upper horizontal portionof the plot) that allows light to pass to a shutter mechanism of thecamera. Plot 1820 shows the movement of an edge of a first shutter bladefrom an initial position (represented by the initial horizontal portionof the plot) that blocks light from an imaging sensor of the camera to asecond stopped position (represented by the second horizontal portion ofthe plot). In the stopped position, the first shutter blade does notblock light from passing to the imaging sensor. A diagonal portionconnecting the two horizontal portions represents the movement of thefirst shutter blade from a position fully obstructing light through atime where the imaging sensor is partially blocked by the first shutterblade to a time where the first shutter blade is no longer obstructinglight to the imaging sensor. Initiation of the movement of a firstshutter blade may occur in a variety of ways. In one example, a firstshutter blade occurs as a result of a magnet that holds the shutterblade in place being released. In such an example, a magnet may bereleased by a magnet release signal. Plot 1825 shows the movement of anedge of a second shutter blade from an initial open position(represented by the initial horizontal portion of the plot) to a secondstopped position (represented by the second horizontal portion of theplot) at which the second shutter blade fully blocks light from the lensto the imaging sensor. A diagonal portion of the plot connecting the twohorizontal portions represents the movement of the second shutter bladefrom a position that does not obstruct light to the sensor through atime where the shutter blade partially obstructs light to the sensor toa time of fully blocking light to the sensor. Dashed line 1830 marks thetime at which the edge of the first shutter blade clears the imagingsensor such that it no longer blocks light to the imaging sensor. Inthis example, this time occurs prior to the first shutter blade stoppingmovement. Dashed line 1835 marks the time at which the leading edge ofthe second shutter blade starts to obstruct light from passing to theimaging sensor. In this example, this time occurs at a point after thesecond shutter blade has begun movement. The time 1840 between dashedlines 1830 and 1835 is the time that the imaging sensor is fullyunobstructed by the shutter blades. Plot 1845 shows an optional voltagechange plot associated with time period 1840. Plot 1850 shows a voltagechange plot of a conventional X-Sync signal of the camera that beginswith a voltage change at about the time of the first shutter bladestopping movement and ends with a voltage change at the time of thesecond shutter blade stopping movement.

Plot 1855 represents a wireless transmission signal used to communicatesynchronization information from a camera to one or more photographiclighting devices according to any one of the implementations forinitiating light emission described herein. Plot 1855 includesrepresentations for a first synchronization transmission 1860, and asecond synchronization transmission 1862, a data transmission 1864.First synchronization transmission 1860 is a transmission includinginstructions for synchronizing the initiation of light emission by aphotographic lighting device according to any one or more of theembodiments and implementations of timing of emission initiationdiscussed herein. Second synchronization transmission 1862 is anoptional transmission. In this example, second synchronizationtransmission 1862 is for receipt by one or more lighting devices notassociated with a functionality for early synchronization with timedelay factors. Second synchronization transmission 1862 provides such adevice with a wireless light emission initiation direct signal such thatthe time of initiation is at about the time of receipt of the wirelesstransmission (e.g., at the time of X-sync or another predeterminedtime). In one example, transmissions 1860 and 1862 are configured tohave light emission initiation by their corresponding lighting devicesoccur at the same time. In another example, transmissions 1860 and 1862are configured to have light emission initiation at different times.Data transmission 1864 is also an optional transmission. An earlytransmitted data transmission can provide information about the imageacquisition (e.g., other than timing information), information about thecamera, and any combinations thereof to a remote lighting device. Inthis example, data transmission 1864 transmits information regardingpower settings obtained from the power set command 1805.

Plot 1870 shows a light emission intensity profile of a lighting device.Dashed line 1872 marks the intensity level above which the lightemission of the lighting device is detectable by the imaging sensor overambient lighting. Initial critical point 1874 is the point on the lightemission profile at which the light emission is first detectable by theimaging sensor above the ambient light. Terminal critical point 1876 isthe point on the light emission profile at which the light emission islast detectable by the imaging sensor above the ambient light. Thehashed area under the light emission curve represents the light emissionthat is detectable by the imaging sensor. Light emission is initiatedafter the first shutter blade begins to allow light to pass to theimaging sensor and before the first shutter blade stops movement.

In this implementation, the data signal 1805 is detected. In thisexample, this signal 1805 is utilized to provide data for datatransmission 1864. Signal 1805 is also used as an indicator that thenext major drop in clock line 1808 is a reliable predictor signal thatcan be utilized in timing the initiation of one or more lightingdevices. The initiation of the drop in the voltage of the clock lineutilized as the predictor signal 1812. Based on the occurrence ofpredictor signal 1812, first synchronization transmission 1860 iscommunicated to a lighting device. First synchronization transmission1860 includes instructions for initiating light emission of the lightingdevice such that light emission is initiated as shown in plot 1870. Inthis example, light emission is initiated prior to X-sync and after thefirst shutter blade begins to expose the sensor. The initial criticalpoint 1874 and terminal critical point 1876 each occur within the timewindow 1840. As discussed above, light emission can be initiated suchthat critical point 1874 occurs at any of a variety of times withrespect to an X-sync time and/or the time represented by line 1830. Itis contemplated that the examples discussed above could apply to thetiming of initial critical point 1874.

As is shown with respect to FIG. 18, first synchronization transmissioninitiates at a time 1885 after the occurrence of predictor signal 1812and at a time 1890 before the first shutter blade clears the sensor(i.e., the time shown by line 1830). The instructions for initiatinglight emission included in synchronization transmission 1860 may utilizethe total time between time 1880 and time 1830, the time 1885, the time1890, a time delay factor, known delays due to transmission, knowndelays due to excitation of lighting device, and/or other factors indetermining the time 1885 for transmission after predictor signal and/orin determining a time delay factor included in the instructions for whenthe light emission initiation occurs after receipt of the transmission1860. Various calibration procedures were discussed above. Additionalcalibration procedures are discussed further below (e.g., with respectto FIGS. 19 and 20).

FIG. 19 illustrates an additional exemplary implementation of acalibration procedure for determining a time calibration value for usein determining the timing of light emission initiation. At step 1905 apredictor signal and/or event is detected. At step 1910 the time ofoccurrence of X-sync (e.g., first shutter blade stopping movement)and/or the time of occurrence of the first shutter blade clearing thesensor are determined. In one example, at step 1915 the time from thepredictor signal and/or event to the time of occurrence of X-sync isdetermined. In another example, at step 1915 the time from the predictorsignal and/or event to the time of occurrence of the first shutter bladeclearing the sensor is determine. The resultant data value from step1915 is stored as a calibration value for use in calibratingsynchronization as discussed herein.

FIG. 20 illustrates another exemplary implementation of a calibrationprocedure. At step 2005, a calibration image acquisition sequence isinitiated. The time of start of movement of the second shutter blade ofa camera body is determined at step 2010. In one example, a signal maybe provided by a camera indicating the start of movement of the secondshutter blade. At step 2015, the shutter speed of the image acquisition,the shutter blade travel time for the camera, and the time from theoccurrence of a predictor signal and/or event to the start of movementof the second shutter blade are used to determine the time from thepredictor signal and/or event to the stopping of movement of the firstshutter blade (e.g., X-sync). At step 2020, the resultant value isstored and/or used as a calibration value that can be used to assist intiming the initiation of light emission. In one example, step 2015further includes determining the time from the stopping of movement ofthe first shutter blade to the start of movement of the second shutterblade utilizing the shutter speed and the shutter blade travel time forthe camera. In one such example, the shutter speed indicates the timebetween the start of movement of the first shutter blade and the startof movement of the second shutter blade. Using the blade travel time ofthe first shutter blade from start to finish and subtracting this fromthe shutter speed indication, the time from the stopping of movement ofthe first shutter blade to the start of movement of the second shutterblade can be determined. Blade travel times may vary from camera modelto camera model and can be determined by analysis and or from literaturevalues. The shutter speed of a camera during an image acquisition can bedetermined in a variety of ways. Example ways to determine shutter speedinclude, but are not limited to, detection via an external connector ofthe camera (e.g., to which a wireless communication functionality isconnected, see FIGS. 35 and 36 below for an example), observation of auser interface of the camera, and any combinations thereof. Blade traveltimes for one or more cameras can be stored for retrieval duringcalibration and/or implementation of any one or more of the embodimentsand/or implementations discussed herein.

Step 2015 may further include determining the time from the predictorsignal and/or event to the stopping of movement of the first shutterblade utilizing the time from the occurrence of the predictor signaland/or event to the start of movement of the second shutter blade andthe time from the stopping of movement of the first shutter blade to thestart of movement of the second shutter blade. In one aspect ofcalibration, analysis of images at various adjustments to the time froma predictor signal to X-sync can be used in various implementations todetermine an approximation of the time that the first shutter bladeclears the sensor by viewing any clipping that may occur (e.g.,utilizing values for time from initiation of light emission to initialcritical point for a given flash, such as provided by literature valuesfrom manufacturer).

Determination of time of first shutter blade clearing the sensor can bemade in a variety of ways. In one example, a shutter speed setting canbe made such that an X-sync signal can be detected and the time from aprior event (e.g., triggering image acquisition) to the initiation ofX-sync signal can be measured. A shutter speed setting can be made suchthat an FP-sync signal can be detected and the time from the same priorevent to the initiation of the FP-sync signal can be measured. Thecenterpoint difference can be determined. For example, if the time toX-sync is 50 milliseconds and the time to FP-sync is 45 milliseconds,the time from the FP-sync signal to the X-sync signal is 5 milliseconds.Using the camera in an FP-sync mode, a wireless communication device isconnected to the camera. The wireless communication device has thecapability of including a delay in the time from receiving the FP-syncsignal from the camera and initiating a remote light emission. The delayis adjusted in successive image acquisitions and the images analyzed todetermine when clipping is stopped in the image. The delay at that pointis used to determine the time from the initiation of FP-sync signal tothe time of clearing the sensor. The time between FP-sync and otherpredictor signals can be measured and used to determine the time betweenthe predictor signal and the time of the first shutter blade clearingthe sensor.

As discussed above, calibration tables can be stored for use (e.g.,including calibration values for one or more cameras). Additionally,calibration can occur dynamically at or near the time of imageacquisition.

FIG. 21 illustrates one exemplary embodiment of a procedure fordetermining a type of synchronization to implement based on shutterspeed. At step 2105, the shutter speed of the camera is identified. Atstep 2110, it is determined if the shutter speed is so fast that thetime between the initial critical point for a profile of a lightingdevice and the terminal critical point for that device that the imagingwindow between the first blade clearing the sensor and the secondshutter blade starting to obstruct the sensor is smaller than the timebetween critical points. If the imaging window is smaller than thedifference in critical points, unacceptable clipping may occur in someexamples. In such a case, at step 2110, the method proceeds to step2115. If the difference in time of the critical points fits in theimaging window for the shutter speed, the method proceeds to step 2120.At step 2115, a synchronization is initiated that will utilize a lightemission of the FP-type, as discussed above. At step 2120, it isdetermined if the shutter speed is less than or equal to the maximumX-sync shutter speed for the camera (e.g., as rated by the manufacturer,as determined by analysis of images acquired at various shutter speeds).If the shutter speed is less than or equal to maximum X-sync value, themethod proceeds to step 2125. If the shutter speed is greater thanmaximum X-sync, the method proceeds to step 2130. At step 2125, aconventional X-sync signal is utilized to initiate light emission. Atstep 2130, two options are provided in this exemplary implementation forinitiating a light emission. In one example, the determination betweenthe two options is made by determining if an FP-sync signal is availablefrom the camera. If an FP sync signal is not available, the methodproceeds to step 2135. If an FP sync signal is available, the methodproceeds to step 2150. At step 2135, a Power Set Command is detected ona data signal line of the camera. At step 2140, the time from the PowerSet Command and a desired time for initiation of light emission isdetermined using one or more of the implementations and/or embodimentsdiscussed herein. At step 2145, a non-FP-type light emission isinitiated. At step 2150, an FP-sync signal is detected. At step 2155,the time from the FP-sync signal and the time of desired light emissioninitiation is determined using one or more of the implementations and/orembodiments discussed herein. At step 2160, a non-FP-type light emissionis initiated.

FIG. 22 illustrates exemplary timing plots for an image acquisitionutilizing a camera and one or more flash devices synchronized to imageacquisition. Timing plot 2205 represents a camera clock signal measuredin voltage (y-axis) over time (x-axis). Timing plot 2205 shows a voltagechange 2210 at the beginning of a signal related to the magnet releaseassociated with the first shutter blade of the camera. In this example,the voltage change 2210 was detectable as reliable predictor of when thefirst shutter blade of the camera stopped movement (e.g., at theX-synch). Timing plot 2215 represents the X-sync signal of the camera asa voltage (y-axis) over time (x-axis). Timing plot 2215 shows a voltagechange 2220 representing the start of the X-sync (the point in time thatthe first shutter blade of the camera stopped moving. Timing plot 2225represents a light emission intensity (y-axis) profile over time(x-axis) for the synchronized lighting device. In this example, lightemission was initiated in response to the X-sync signal. The lightemission curve 2230 initiates in time fully after the beginning of theX-sync signal. Such a synchronization system and method is typicallylimited to flash synchronization at shutter speeds of 1/250^(th) andslower (for cameras with fast shutter blade travel times) or 1/200^(th)and slower (for cameras with slower shutter blade travel times).

FIG. 23 illustrates another set of timing plots for an exemplary imageacquisition using an early synchronization. This set of timing plotsshows events earlier in the time of the process after triggering theimage acquisition. Timing plot 2305 represents the clock information ofthe camera. Timing plot 2310 represents a camera data signal. Timingplot 2315 represents a monitoring of the X-sync line of the camera.Timing plot 2320 represents a light intensity profile over time. Afterthe image acquisition is triggered, but before the mirror moves out ofthe light path to the shutter mechanism, the clock signal line 2305 anddata signal line 2310 of the camera indicate pulses of information 2325.These pulses represent TTL power setting commands. At a time after themirror stops movement, the magnet release signal is indicated as avoltage change 2330 on the camera clock signal line 2305. The timebetween the magnet release signal 2330 and a time associated with thestopping of the first shutter blade movement (indicated as a voltagechange 2335 on the X-sync line 2315) was pre-learned by an earlysynchronization system (such as early synchronization system 1300). Athreshold comparator of the synchronization system detected pulses 2325and with reference to stored information regarding the camera (e.g.,learned during a calibration), a processor identified pulses 2325 as anindication that the next larger voltage change to occur on the clockline 2305 would represent a mirror release signal. The thresholdcomparator then detected the magnet release signal 2330, the processorreferenced a memory for stored information regarding the time from thispredictor signal and X-sync for this camera, and the processorreferenced a calibration value including information for the timing oflight emission initiation. The processor generated a light emissioninitiation signal in time to have light emission initiate at a time 2340after the first shutter blade started to allow light to pass to thesensor and before the first shutter blade stopped moving at 2335. Clockline 2305, data line 2310, and X-sync line 2315 were detectable via ahot shoe connector of the camera. FIG. 23 also shows post imageacquisition data transfer (e.g., via the camera hot shoe) on clock line2305 at voltage changes 2345 and on data line 2310 at voltage changes2350.

FIG. 24 illustrates another set of timing plots for yet anotherexemplary image acquisition. This image acquisition utilized aprediction of the first shutter blade movement stop time 2405 (seen asX-sync start on X-sync line 2410) from a magnet release signal detectedfrom clock line 2415, as discussed in various examples above. From thedetermination of when the first shutter blade would stop moving a zerocalibration was applied. This resulted in light emission initiation of alighting device occurring at time 2420. As seen on timing plot 2425 ofthe light emission intensity over time, light emission initiation 2420occurred approximately at the same time as the first shutter bladestopping movement (as opposed to prior to this time). Timing plot 2425also shows a theoretically derived initial critical point 2430 for thelight emission profile.

FIG. 25 illustrates another set of timing plots for still anotherexemplary image acquisition. This image acquisition utilized aprediction of the first shutter blade movement stop time 2505 (seen asX-sync start on X-sync line 2510) from a magnet release signal detectedfrom clock line 2515. From the determination of when the first shutterblade would stop moving a calibration of 200 microseconds applied. Thisresulted in light emission initiation of a lighting device occurring attime 2520. As seen on timing plot 2525 of the light emission intensityover time, light emission initiation 2520 occurred before the firstshutter blade stopped movement (by approximately 200 microseconds).

FIG. 26 illustrates another set of timing plots for still anotherexemplary image acquisition. This image acquisition utilized aprediction of the first shutter blade movement stop time 2605 (seen asX-sync start on X-sync line 2610) from a magnet release signal detectedfrom clock line 2615. From the determination of when the first shutterblade would stop moving a calibration of 400 microseconds applied. Thisresulted in light emission initiation of a lighting device occurring attime 2620. As seen on timing plot 2625 of the light emission intensityover time, light emission initiation 2620 occurred before the firstshutter blade stopped movement (by approximately 400 microseconds).

FIG. 27 illustrates another set of timing plots for still yet anotherexemplary image acquisition. These timing plots include a timing plot2705 of a camera clock line, a timing plot 2710 of a camera data line, atiming plot 2715 of a camera X-sync line, and a timing plot 2720representing radio frequency signal over time of wireless transmissionsassociated with image acquisition and the synchronization of a remotelighting device having a wireless communication functionality equippedwith an early synchronization system (such as system 1300) and anotherremote lighting device having a wireless communication functionalityconfigured only to initiate light emission upon reception of traditionalsynchronization signal. In this exemplary implementation, TTL commanddata pulses 2725 were detected. Power control information wastransmitted via radio frequency to one or more of the remote devices asshown by RF pulses 2730. Pulses 2725 were also used to determine thatthe next full voltage drop on line 2705 would represent a predictorsignal (in this case a magnet release signal) as shown by the voltagedrop 2735. The known time to time when the first shutter blade stoppedmovement (indicated by voltage drop 2740) and a calibration value wasutilized to determine when light emission initiation should occur. Thetime to transmit radio frequency to the remote devices was utilized todetermine a timing code to be wirelessly transmitted to the wirelessreception device capable of managing early synchronization data. Forexample, if the time to first shutter blade stopping movement 5milliseconds (ms), the calibration value is 400 microseconds, and thetime to transmit via RF is 500 microseconds, the RF transmission to theremotes would need to occur at approximately 4.1 milliseconds from thedetected predictor signal. In another example (as illustrated in FIG.27), a timing code delay feature can be utilized. A timing code delayfeature can instruct the receiving wireless device to delay for a periodof time from receipt before generating a light emission initiationsignal to the flash device. The receiving wireless device hasappropriate circuitry and/or machine readable instructions to performsuch a delay upon instruction from the timing code. In such an example(using the numbers from above) the camera-side wireless device cantransmit the timing code earlier than above and still have the lightemission initiate at the proper time. For example, a timing code delayof 2 milliseconds would allow the RF signal to be transmitted atapproximately 2.1 milliseconds from the detected predictor signal. It isnoted that this example does not take into account circuitry delay atthe receiving end. It is contemplated that a receiving wirelessdevice/early flash synchronizing device and/or the camera-side wirelessdevice may include circuitry, memory, and/or instructions for factoringin known delays due to circuitry transmission. In one exemplary aspect,transmitting an RF timing code with delay information early can allowfor multiple RF transmissions (e.g., for multiple zoned remotes,different types of remotes, etc.) with appropriately varied delays priorto the desired light emission initiation time. Referring again to theexample shown in FIG. 27, an RF pulse 2745 was transmitted with a timingcode delay to a remote configured to manage the delay data. A second RFpulse 2750 was transmitted at a time that would have the light emissioninitiation from a remote flash with a standard reception device occur atthe desired initiation time (e.g., transmitted approximately 4.1milliseconds from the detected predictor signal, using the above exampletheoretical timing data). In this way, multiple types of receptiondevices may be utilized to synchronize light emission initiation.

FIG. 28A illustrates a photograph 2805 acquired using flash photographywith a shutter speed of 1/200^(th) of a second using a radio frequencywireless system to synchronize a flash device with the X-sync signal.FIG. 28B illustrates a photograph 2810 acquired using flash photographywith a shutter speed of 1/200^(th) of a second using a radio frequencywireless system configured to initiate light emission after the firstshutter blade has moved to a position that begins to allow light to passto the imaging sensor and before the first shutter blade stops movement.

FIG. 29A illustrates a photograph 2905 acquired using flash photographywith a shutter speed of 1/250^(th) of a second using a radio frequencywireless system to synchronize a flash device with the X-sync signal.FIG. 29B illustrates a photograph 2910 acquired using flash photographywith a shutter speed of 1/250^(th) of a second using a radio frequencywireless system configured to initiate light emission after the firstshutter blade has moved to a position that begins to allow light to passto the imaging sensor and before the first shutter blade stops movement.

FIG. 30A illustrates a photograph 3005 acquired using flash photographywith a shutter speed of 1/320^(th) of a second using a radio frequencywireless system to synchronize a flash device with the X-sync signal.FIG. 30B illustrates a photograph 3010 acquired using flash photographywith a shutter speed of 1/320^(th) of a second using a radio frequencywireless system configured to initiate light emission after the firstshutter blade has moved to a position that begins to allow light to passto the imaging sensor and before the first shutter blade stops movement.

FIG. 31A illustrates a photograph 3105 acquired using flash photographywith a shutter speed of 1/400^(th) of a second using a radio frequencywireless system to synchronize a flash device with the X-sync signal.FIG. 31B illustrates a photograph 3110 acquired using flash photographywith a shutter speed of 1/400^(th) of a second using a radio frequencywireless system configured to initiate light emission after the firstshutter blade has moved to a position that begins to allow light to passto the imaging sensor and before the first shutter blade stops movement.

FIG. 32A illustrates a photograph 3205 acquired using flash photographywith a shutter speed of 1/500^(th) of a second using a radio frequencywireless system to synchronize a flash device with the X-sync signal.FIG. 32B illustrates a photograph 3210 acquired using flash photographywith a shutter speed of 1/500^(th) of a second using a radio frequencywireless system configured to initiate light emission after the firstshutter blade has moved to a position that begins to allow light to passto the imaging sensor and before the first shutter blade stops movement.

FIGS. 28A, 29A, 30A, 31A, and 32A show an increasing level of “clipping”(image darkening at one edge as the shutter speed becomes faster. At1/200^(th) of a second, the standard X-sync shows a bit of clipping,which may be acceptable (e.g., cropping may eliminate the darkening atthe bottom of the image). However, at 1/250^(th) of a second and faster,the standard X-sync shows much greater levels of clipping. In contrast,FIGS. 28B, 29B, 30B, 31B, and 32B illustrate examples of much higherperformance at higher sync speeds using an exemplary process of earlysynchronization with detection of a predictor signal and initiation oflight emission after the first shutter blade has moved to a positionthat begins to allow light to pass to the imaging sensor and before thefirst shutter blade stops movement. The level of visually detectabledarkening at the edges is not serious until 1/400^(th) and faster. Thisclipping could possibly be calibrated out of the images by adjusting thecalibration offset value.

FIG. 33 illustrates one example of a camera 3305 having a built-in flashdevice 3310. In one exemplary implementation, camera 3305 may includeappropriate circuitry and/or instructions capable of execution by one ormore circuit elements of camera 3305 that generate a light emissioninitiation signal such that light is emitted by flash device 3310 aftera first shutter blade of camera 3305 has begun to allow light to pass toan imaging sensor of camera 3305 but before the first shutter bladestops movement. The circuitry and/or instructions may also be configuredto implement any one or more of the other aspects of the implementationand embodiments described herein.

FIG. 34 illustrates one example of a camera 3405 having a built-in radiofrequency wireless transceiver (not shown). The transceiver may beutilized to wirelessly communicate with one or more remote devices via aradio frequency transmission, such as transmission 3410. A remotelighting device 3415 is shown. Remote lighting device 3415 is an exampleof a hot shoe mountable speedlight flash device. The built-intransceiver of camera 3405 may be utilized to wirelessly communicatewith remote lighting device 3415 and/or one or more other types oflighting devices (e.g., one or more other hot shoe mountable lights, oneor more studio strobe lighting devices). Remote lighting device 3415 isshown connected to an external wireless device 3420. It is contemplatedthat any one or more remote devices may include an internal wirelessfunctionality. In one exemplary implementation camera 3405 may includeappropriate circuitry and/or instructions capable of execution by one ormore circuit elements of camera 3405 that generate a light emissioninitiation signal such that the light emission initiation signal iswirelessly transmitted to wireless device 3420 for communication tolighting device 3415 such that light emission is initiated by lightingdevice 3415 after a first shutter blade of camera 3405 has begun toallow light to pass to an imaging sensor of camera 3405 but before thefirst shutter blade stops movement. In another exemplary implementation,camera 3405 may include appropriate circuitry and/or instructionscapable of execution by one or more circuit elements of camera 3405(e.g., circuitry and/or machine executable instruction associated withthe internal wireless capability of camera 3405) that detect a predictorsignal and/or a predictor event of camera 3405 from which the time tothe first shutter blade stopping movement can be determined. Using thepredictor signal and/or predictor event, a light emission initiationsignal can be generated such that light emission initiates after thefirst shutter blade begins to allow light to pass to an imaging sensorbut before the first shutter blade stops movement. Additional aspectsand embodiments of using a predictor signal and/or a predictor event arediscussed above. The circuitry and/or instructions may also beconfigured to implement any one or more of the other aspects of theimplementation and embodiments described herein.

FIG. 35 illustrates one example of a camera 3505 having an externalwireless device 3510 connected via a hot shoe connector of camera 3505.External wireless devices are known. In one aspect, an external wirelessdevice may be configured to communicate data (e.g., camera and/or flashdata) to and/or from a camera via one or more of the contacts of a hotshoe connector. Examples of external wireless devices configured forconnection to a camera hot shoe and methodologies for communicating viaa hot shoe connector are discussed in further detail in copending U.S.patent application Ser. No. 12/129,402, filed on May 29, 2008, thedisclosure of which is incorporated herein by reference in its entirety.

Camera 3505 may utilize wireless device 3510 to wireless communicate viaa wireless transmission, such as transmission 3515, with one or moreremote devices. A remote lighting device 3520 is shown connected via ahot shoe connector to a wireless device 3525. As discussed above, acamera may communicate with one or more remote lighting devices forsynchronizing the one or more lighting devices to image acquisition. Theone or more remote lighting devices may each include an externalwireless functionality, an internal wireless functionality, or anycombination thereof. In one exemplary implementation, camera 3505(and/or wireless device 3510) may include appropriate circuitry (and/orinstructions capable of execution by one or more circuit elements) thatgenerate a light emission initiation signal such that the light emissioninitiation signal is wirelessly transmitted to wireless device 3525 forcommunication to lighting device 3520 such that light emission isinitiated by lighting device 3520 after a first shutter blade of camera3505 has begun to allow light to pass to an imaging sensor of camera3505 but before the first shutter blade stops movement. In anotherexemplary implementation, camera 3505 (and/or wireless device 3510) mayinclude appropriate circuitry and/or instructions capable of executionby one or more circuit elements that detect a predictor signal and/or apredictor event of camera 3505 from which the time to the first shutterblade stopping movement can be determined. Using the predictor signaland/or predictor event, a light emission initiation signal can begenerated such that light emission initiates after the first shutterblade begins to allow light to pass to an imaging sensor but before thefirst shutter blade stops movement. Additional aspects and embodimentsof using a predictor signal and/or a predictor event are discussedfurther above. The circuitry and/or instructions may also be configuredto implement any one or more of the other aspects of the implementationand embodiments described herein.

FIG. 36 illustrates one example of a camera 3605 having an externalwireless device 3610 connected via a hot shoe connector. Camera 3605 mayutilize wireless device 3610 to wirelessly communicate (e.g., via atransmission 3615) to one or more remote lighting devices 3620 having awireless functionality 3625 (e.g., an internal wireless functionalityand/or external wireless functionality, as shown). A hot shoe mountableflash device 3630 is connected to a second hot shoe connector ofwireless device 3610. In one exemplary implementation, one or moreremote lighting devices 3620 and/or flash device 3630 may haveassociated light emission initiated after a first shutter blade ofcamera 3605 begins to allow light to pass to an imaging sensor of camera3605 but before the first shutter blade stops movement. In one suchimplementation, wireless device 3610 may include appropriate circuitry(and/or instructions capable of execution by one or more circuitelements) that detect a signal and/or event of camera 3605 from whichthe timing of initiation of the light emission can be determined and aninitiation signal generated accordingly. The initiation signal may thenbe utilized to initiate a light emission by one or more lighting devices3620 and/or flash device 3630. Additional aspects and embodiments ofusing a predictor signal and/or a predictor event are discussed above.The circuitry and/or instructions may also be configured to implementany one or more of the other aspects of the implementation andembodiments described herein.

FIG. 37 illustrates an exemplary early synchronizer system 3700. In oneexemplary aspect, early synchronizer system 3700 may provide an abilityto initiate light emission at a time after a first shutter blade of acamera moves such that light begins to be allowed to pass to an imagingsensor of the camera and before the first shutter blade of the camerastops movement. In one example, early synchronizer system 3700 includesone or more components that are internal to a camera. In anotherexample, one or more components of early synchronizer system 3700 may beadded to a camera that does not already have an ability to initiatelight emission at a time after a first shutter blade of the camera movessuch that light begins to be allowed to pass to an imaging sensor of thecamera and before the first shutter blade of the camera stops movement.In yet another example, early synchronizer system 3700 includes one ormore components that are part of a photographic wireless communicationdevice (e.g., a transmitter, receiver, and/or transceiver associatedwith a camera and/or one or more remote devices). In one such example,at least a portion of the photographic wireless communication device isinternal to a camera. In another such example, at least a portion of thephotographic wireless communication device is external to a camera.

Early synchronizer system 3700 includes a processor 3705. Processor 3705may be a shared processing element. In one example, processor 3705 isshared with other functionality of a camera. In another example,processor 3705 is shared with other functionality of a photographicwireless communication device. One of the functionalities of processor3705 may include generation of a light emission initiation signal 3710for initiating light emission of one or more lighting devices 3715. Inan alternative implementation, early synchronizer system 3700 mayinclude a light emission initiation signal generator separate fromprocessor 3705. Processor 3705 is configured to be in electricalcommunication with circuitry and/or electronics 3720 of a camera. In oneexample, processor 3705 is connected electrically (e.g., via electricalwiring and/or other electrical contacts) to circuitry and/or electronics3720. In another example, processor 3705 is connected to one or moreconnectors (not shown) that are configured to be connected to circuitryand/or electronics 3720 of a camera. Connectors for electricallyconnecting an external device to internal circuitry and/or electronicsof a camera are known. Examples of such connectors include, but are notlimited to, a flash synchronization connector, a hot shoe connector, aPC flash synchronization connector (note the term PC as used in thisexample refers to the photographic industry standard “PC connector” andnot to a “personal computer”); a Universal Serial Bus (“USB”) connector,a FireWire connector, a connector proprietary to a given cameramanufacturer, a motor-drive connector, and any combinations thereof.

Early synchronization system 3700 may optionally include a predictorsignal detector 3725 electrically connected and/or configured to beelectrically connected to circuitry and/or electronics 3720 fordetecting (e.g., receiving) a predictor signal and/or an indication of apredictor event of the camera. Predictor signal detector 3725 mayinclude circuitry and/or machine executable instruction configured todetect the predictor signal and/or event and communicate the detectionto processor 3705 and/or other light emission initiation signalgenerator functionality. In one example, predictor signal detector 3725includes a threshold comparator. In another example, predictor signaldetector 3725 includes an input/output (I/O) port of a processor element(e.g., processor element 3705. In one such example, at least a portionof predictor signal detector 3725 may share common components withprocessor 3705.

Early synchronization system 3700 includes a memory 3730. Memory 3730may be any memory device capable of storing data and/or otherinformation. Examples of a memory device include, but are not limitedto, a random access memory, a read only memory, a flash memory, ahard-drive memory device, an optical memory device, and any combinationsthereof. Memory 3730 is shown in electrical communication with processor3705. In an alternative implementation memory 3730 may be directlyand/or indirectly in electrical communication with (and/or be configuredto be electrically connected to) any one or more additional componentsof early synchronization system 3700 that may require informationstorage capability. Memory 3730 is shown as a separate component. It iscontemplated that memory 3730 and/or any other component of earlysynchronization system 3700 may have any portion thereof shared withanother component. It is also contemplated that memory 3730 and/or anyother component of early synchronization system 3700 may also be dividedinto more than one component element. Memory 3730 may includeinformation (e.g., in one or more tables) for example, but not limitedto, calibration time values, other calibration values not in timeincrements, data related to a camera model, data related to the timebetween a predictor signal and/or event and the time of the firstshutter blade stopping movement, one or more time delay factors, othercalibration values as discussed above, shutter speed correlations,information related to instructions for initiating light emission afterthe first shutter blade begins to expose the image acquisition sensor tolight and before X-sync associated with the first shutter blade stoppingmovement, and any combinations thereof.

Early synchronization system 3700 may optionally include one or moredata inputs 105. One or more data inputs 105 may be in electricalcommunication and/or be configured to be electrically connected toprocessor 3705, memory 3730, and/or other components of earlysynchronization system 3700. Example data inputs include, but are notlimited to, a dial, a trigger, a touch screen, a USB connector, anotherdata connector, and any combinations thereof. In one example, a USBconnector may connect to a computing device (e.g., a general computingdevice, such as a laptop or desktop computer) having thereon a softwareprogram for interfacing with early synchronization system 3700. In onesuch example, the software program may provide a graphical userinterface for inputting data (e.g., calibration time values, othercalibration values not in time increments, data related to a cameramodel, data related to the time between a predictor signal and/or eventand the time of the first shutter blade stopping movement, one or moretime delay factors, etc.). Such data may be stored in memory 3730.

One or more data inputs 3735 may be accompanied by a data/informationoutput (not shown) for conveying information from system 3700 (e.g., toa user). Examples of a data/information output include, but are notlimited to, an LED, an LCD, a display screen, an audio device, and anycombinations thereof.

FIG. 38 illustrates multiple views of a photographic wirelesscommunication device 3805. Wireless communication device 3805 includesan internal transmitter component (not shown) for wirelesslytransmitting information to one or more remote devices and an internalantenna component (not shown). Wireless communication device 3805 alsoincludes components of an early synchronization system, such as system3700 of FIG. 37. Wireless communication device 3805 includes a first hotshoe connector 3810 configured to connect to a hot shoe connector of acamera and provide electrical communication with the circuitry and/orelectronics of the camera (e.g., communication with data, clock, and/orX-sync signals). Wireless communication device 3805 also includes asecond hot shoe connector 3815 configured to allow another device havinga hot shoe connector to be connected to the top of wirelesscommunication device 3805. In one example, a speedlight flash device maybe connected to hot shoe connector 3815. Wireless communication device3805 also includes a tightening ring 3820 for securely connecting hotshoe connector 3810 to a corresponding hot shoe of a camera.

Wireless communication device 3805 includes a USB data connector 3825for inputting and outputting information from wireless communicationdevice 3805 and the early synchronization functionality therein. Aninput 3830 and an input 3835 provide information input and control towireless communication device 3805. Wireless communication device 3805includes an optical output element 3840 for outputting information.

In one exemplary implementation, a predictor signal is detected throughone or more of the contacts of hot shoe connector 3810 from a cameraconnected thereto. Wireless communication device 3805 may also receivevia hot shoe connector 3810 data representing the model of the cameraand the shutter speed of operation of the camera. A processor ofwireless communication device 3805 accesses a memory having acorrelation between the data representing the model of the camera andthe corresponding time from the predictor signal to the time of thefirst shutter blade of the camera stopping movement. The processor alsoaccesses the memory for data representing a calibration value for thereceived shutter speed of operation of the camera. Based on thecalibration value, the known time from predictor signal to first shutterblade stopping for the model of camera, and the time of detection of thepredictor signal, the processor generates a light emission initiationsignal and transmits the signal to one or more wireless receptiondevices each associated with a remote lighting device. In this example,the processor of wireless communication device 3805 takes into accountthe time necessary for wireless communication and circuitrycommunication in generating the light emission initiation signal suchthat initiation of the light emission will occur at the desired timebetween the first shutter blade of the camera moving such to allow lightto start to pass to the sensor and the first shutter blade stoppingmovement.

In yet another exemplary implementation, a wireless remote device may beconfigured to handle varying times between light emission initiation andinitial critical point for various lighting devices. In one example, aspeedlight may have a time from flash initiation to initial criticalpoint of 40 microseconds and a studio strobe flash may have a time fromflash initiation to initial critical point of 100 microseconds. Awireless early synchronization device that is remote from a camera(e.g., has a remote flash device connected thereto) may have a memorywith data stored for varying times for varying flashes. For example,when a speedlight is connected (e.g., to a hot shoe connector) thesynchronization device may utilize an offset based on a value stored fora speedlight. In another example, when a strobe is connected (e.g., to aminiphone connector) the synchronization device may utilize an offsetbased on a value stored for a strobe flash. The offsets at the receiverside can be utilized to ensure that when a desired time for lightinitiation is determined (as discussed above) and transmitted to remotelight devices, varying light devices contribute detectable light to thescene at the same time (e.g., their initiation times are offset fromeach other so that their initial critical points occur at the sametime).

It is to be noted that the aspects and embodiments described herein maybe conveniently implemented using one or more circuit elements asdescribed above and/or included in one or more of a camera, a wirelesscommunication device, and a lighting device programmed according to theteachings of the present specification. Appropriate software coding forcombination with appropriate circuitry and other electronic componentscan readily be prepared by skilled programmers based on the teachings ofthe present disclosure, as will be apparent to those of ordinary skillin the software art.

Such software may be a computer program product that employs amachine-readable medium. A machine-readable medium may be any mediumthat is capable of storing and/or encoding a sequence of instructionsfor execution by a machine (e.g., a processor and other electricalcomponents of a camera, a wireless communication device, a flash device)and that causes the machine to perform any one of the methodologiesand/or embodiments described herein. Examples of a machine-readablemedium include, but are not limited to, a magnetic disk (e.g., aconventional floppy disk, a hard drive disk), an optical disk (e.g., acompact disk “CD”, such as a readable, writeable, and/or re-writable CD;a digital video disk “DVD”, such as a readable, writeable, and/orrewritable DVD), a magneto-optical disk, a read-only memory “ROM”device, a random access memory “RAM” device, a magnetic card, an opticalcard, a solid-state memory device (e.g., a flash memory), an EPROM, anEEPROM, and any combinations thereof. A machine-readable medium, as usedherein, is intended to include a single medium as well as thepossibility of including a collection of physically separate media, suchas, for example, a collection of compact disks or one or more hard diskdrives in combination with a computer memory.

Exemplary embodiments have been disclosed above and illustrated in theaccompanying drawings. It will be understood by those skilled in the artthat various changes, omissions and additions may be made to that whichis specifically disclosed herein without departing from the spirit andscope of the present invention.

1. A method for synchronizing a photographic lighting device to imageacquisition by a camera, the method comprising: allowing a first shutterblade of the camera to move such that light is allowed to pass to animaging portion of an image acquisition sensor of the camera; andinitiating light emission of the photographic lighting device after thefirst shutter blade begins to expose the image acquisition sensor tolight and before X-sync associated with the first shutter blade stoppingmovement.
 2. A method according to claim 1, wherein the initiating lightemission occurs such that an initial critical point of a flash profileof the photographic lighting device occurs at a point in time afterabout 1 millisecond before the first shutter blade moves to a positionthat no longer obstructs light to the imaging portion of the sensor. 3.A method according to claim 1, wherein the initiating light emissionoccurs such that an initial critical point of a flash profile of thephotographic lighting device occurs at a point in time after about 500microseconds before the first shutter blade moves to a position that nolonger obstructs light to the imaging portion of the sensor.
 4. A methodaccording to claim 1, wherein the initiating light emission occurs suchthat an initial critical point of a flash profile of the photographiclighting device occurs at a point in time after about 250 microsecondsbefore the first shutter blade moves to a position that no longerobstructs light to the imaging portion of the sensor.
 5. A methodaccording to claim 1, wherein the initiating light emission occurs suchthat an initial critical point of a flash profile of the photographiclighting device occurs at a point in time after the first shutter blademoves to a position that no longer obstructs light to the imagingportion of the sensor.
 6. A method according to claim 1, wherein theinitiating light emission occurs such that an initial critical point ofa flash profile of the photographic lighting device occurs at about thetime the first shutter blade moves to a position that no longerobstructs light to the imaging portion of the sensor.
 7. A methodaccording to claim 1, wherein the initiating light emission occurs suchthat an initial critical point of a flash profile of the photographiclighting device occurs before the first shutter blade stops movement. 8.A method according to claim 1, wherein the initiating light emissionoccurs such that a terminal critical point of a flash profile of thephotographic lighting device occurs less than about 500 microsecondsafter a second shutter blade of the camera moves to a point where thesecond shutter blade starts to obstruct light from passing to theimaging portion of the sensor.
 9. A method according to claim 1, whereinthe initiating light emission occurs such that a terminal critical pointof a flash profile of the photographic lighting device occurs less thanabout 250 microseconds after a second shutter blade of the camera movesto a point where the second shutter blade starts to obstruct light frompassing to the imaging portion of the sensor.
 10. A method according toclaim 1, wherein the initiating light emission occurs such that aterminal critical point of a flash profile of the photographic lightingdevice occurs at about the time that the second shutter blade starts toobstruct light from passing to the sensor
 11. A method according toclaim 1, wherein the initiating light emission occurs such that aterminal critical point of a flash profile of the photographic lightingdevice occurs before the time that the second shutter blade starts toobstruct light from passing to the sensor
 12. A method according toclaim 1, further comprising: identifying a camera predictor event and/orsignal that occurs prior to the first shutter blade of the camera movingto a point that allows light to pass to the sensor, the predictor eventand/or signal not being an event or signal for instructing theinitiation of light emission from a photographic lighting device, thepredictor event and/or signal occurring prior to a normal flashinitiation event or signal intended to instruct the light emission ofthe photographic lighting device; and based upon the occurrence of thepredictor event and/or signal, communicating to the photographiclighting device an instruction for the initiating light emission of thephotographic lighting device.
 13. A method according to claim 12,wherein the identifying includes identifying a camera predictor eventand/or signal that is not an event or signal intended for instructingthe initiation of an X-sync flash pulse and occurs prior to the time ofX-sync.
 14. A method according to claim 12, wherein the camera predictorevent and/or signal is a serial data communication of the camera.
 15. Amethod according to claim 14, wherein the serial data communication is apower set command.
 16. A method according to claim 12, wherein thecamera predictor event and/or signal is a drop in a voltage of a clocksignal of the camera.
 17. A method according to claim 12, wherein thecamera predictor event and/or signal is the initiation of a shuttermagnet release signal.
 18. A method according to claim 12, wherein thecamera predictor event and/or signal is the initiation of an FP-synchsignal and the initiating light emission does not include an FP-typeflash emission.
 19. A method according to claim 12, wherein thecommunicating includes delivering the instruction internal to the camerato an internal lighting device.
 20. A method according to claim 12,wherein the communicating includes delivering the instruction via a hotshoe connector of the camera to the photographic lighting device, thephotographic lighting device being positioned in the hot shoe connector.21. A method according to claim 12, wherein the communicating includeswirelessly transmitting the instruction to the photographic lightingdevice.
 22. A method according to claim 21, wherein the wirelesslytransmitting includes a radio frequency transmission.
 23. A methodaccording to claim 21, wherein the instruction is wirelessly transmittedprior to the first shutter blade moving to a position that no longerobstructs light to the imaging portion of the sensor.
 24. A methodaccording to claim 21, wherein the instruction is received by a wirelesscommunications receiver associated with the photographic lighting deviceprior to the first shutter blade moving to a position that no longerobstructs light to the imaging portion of the sensor.
 25. A methodaccording to claim 21, wherein the instruction is wirelessly transmittedprior to the occurrence of the normal flash initiation event or signal.26. A method according to claim 21, wherein the instruction is receivedby a wireless communications receiver associated with the photographiclighting device prior to the occurrence of the normal flash initiationevent or signal.
 27. A method according to claim 12, wherein theinitiating light emission occurs at a time delayed from completion ofthe communicating the instruction.
 28. A method according to claim 27,wherein the instruction includes a delay factor.
 29. A method accordingto claim 27, wherein the instruction includes a precalculated time forthe initiating light emission.
 30. A method according to claim 12,wherein the identifying includes detecting the predictor event and/orsignal external to the camera.
 31. A method according to claim 30,wherein the detecting occurs via a hot shoe connector of the camera. 32.A method according to claim 1, further comprising: detecting a predictorsignal and/or event; determining an amount of time from the occurrenceof the predictor signal and/or event until a desired time for theinitiation of light emission of the photographic lighting device; andtransmitting to the photographic lighting device an instruction for theinitiating light emission of the photographic lighting device at thedesired time.
 33. A method according to claim 32, wherein the detectinga predictor signal and/or event includes identifying the occurrence ofan FP-sync signal of the camera.
 34. A method according to claim 32,wherein the detecting a predictor signal and/or event includesidentifying the occurrence of a power set command of the camera.
 35. Amethod according to claim 32, wherein the detecting a predictor signaland/or event includes identifying the occurrence of a drop in voltage ofa clock signal of the camera, the drop in voltage occurring aftertriggering of image acquisition and prior to the first shutter bladestopping movement.
 36. A method according to claim 32, wherein thedetermining an amount of time includes utilization of a time valuedetermined using a calibration that includes: initiating an imageacquisition sequence; determining a start of movement of a secondshutter blade; and using the shutter speed of the image acquisition, theshutter blade travel time for the camera, the time from the occurrenceof the predictor signal and/or event to the start of movement of thesecond shutter blade to determine the time from the predictor signaland/or event to the stopping of movement of the first shutter blade. 37.A method according to claim 36, wherein the using step includes:determining the time from the stopping of movement of the first shutterblade to the start of movement of the second shutter blade utilizing theshutter speed and the shutter blade travel time for the camera; anddetermining the time from the predictor signal and/or event to thestopping of movement of the first shutter blade utilizing the time fromthe occurrence of the predictor signal and/or event to the start ofmovement of the second shutter blade and the time from the stopping ofmovement of the first shutter blade to the start of movement of thesecond shutter blade.
 38. A method according to claim 32, wherein thedetermining an amount of time includes utilization of a time valuedetermined using a calibration that includes: initiating an imageacquisition sequence; analyzing the resultant image; and modifying anadjustment factor that impacts the value of a delay factor of theinstruction. 39-81. (canceled)
 82. A method for synchronizing aphotographic lighting device to image acquisition by a camera, themethod comprising: allowing a first shutter blade of the camera to movesuch that light is allowed to pass to an image acquisition sensor of thecamera; and initiating light emission of the photographic lightingdevice after the first shutter blade begins to expose the imageacquisition sensor to light and before the shutter travel completionswitch is detected by camera.
 83. A system for synchronizing aphotographic lighting device to image acquisition by a camera, thesystem comprising: means for allowing a first shutter blade of thecamera to move such that light is allowed to pass to an imaging portionof an image acquisition sensor of the camera; and means for initiatinglight emission of the photographic lighting device after the firstshutter blade begins to expose the image acquisition sensor to light andbefore X-sync associated with the first shutter blade stopping movement.84. A system according to claim 83, wherein the means for initiatinglight emission is configured to have light emission initiation occursuch that an initial critical point of a flash profile of thephotographic lighting device occurs at a point in time after about 1millisecond before the first shutter blade moves to a position that nolonger obstructs light to the imaging portion of the sensor. 85-93.(canceled)
 94. A system according to claim 83, further comprising: ameans for identifying a camera predictor event and/or signal that occursprior to the first shutter blade of the camera moving to a point thatallows light to pass to the sensor, the predictor event and/or signalnot being an event or signal for instructing the initiation of lightemission from a photographic lighting device, the predictor event and/orsignal occurring prior to a normal flash initiation event or signalintended to instruct the light emission of the photographic lightingdevice; and a means for communicating, based upon the occurrence of thepredictor event and/or signal to the photographic lighting device aninstruction for the initiating light emission of the photographiclighting device.
 95. A system according to claim 94, wherein the meansfor identifying includes means for identifying a camera predictor eventand/or signal that is not an event or signal intended for instructingthe initiation of an X-sync flash pulse and occurs prior to the time ofX-sync. 96-100. (canceled)
 101. A system according to claim 94, whereinthe means for communicating includes means for delivering theinstruction internal to the camera to an internal lighting device. 102.A system according to claim 94, wherein the means for communicatingincludes means for delivering the instruction via a hot shoe connectorof the camera to the photographic lighting device, the photographiclighting device being positioned in the hot shoe connector.
 103. Asystem according to claim 94, wherein the means for communicatingincludes means for wirelessly transmitting the instruction to thephotographic lighting device.
 104. (canceled)
 105. A system according toclaim 94, wherein the means for identifying includes means for detectingthe predictor event and/or signal external to the camera.
 106. A systemaccording to claim 105, wherein the means for detecting includes a hotshoe connector of the camera.
 107. A system according to claim 83,further comprising: a means for detecting a predictor signal and/orevent; a means for determining an amount of time from the occurrence ofthe predictor signal and/or event until a desired time for theinitiation of light emission of the photographic lighting device; and ameans for transmitting to the photographic lighting device aninstruction for the initiating light emission of the photographiclighting device at the desired time. 108-110. (canceled)
 111. A systemaccording to claim 107, wherein the means for determining an amount oftime includes utilization of a time value determined using a calibrationthat includes: a means for initiating an image acquisition sequence; ameans for determining a start of movement of a second shutter blade; ameans for using the shutter speed of the image acquisition, the shutterblade travel time for the camera, the time from the occurrence of thepredictor signal and/or event to the start of movement of the secondshutter blade to determine the time from the predictor signal and/orevent to the stopping of movement of the first shutter blade.
 112. Asystem according to claim 111, wherein the means for using includes: ameans for determining the time from the stopping of movement of thefirst shutter blade to the start of movement of the second shutter bladeutilizing the shutter speed and the shutter blade travel time for thecamera; and a means for determining the time from the predictor signaland/or event to the stopping of movement of the first shutter bladeutilizing the time from the occurrence of the predictor signal and/orevent to the start of movement of the second shutter blade and the timefrom the stopping of movement of the first shutter blade to the start ofmovement of the second shutter blade
 113. A system according to claim107, wherein the determining an amount of time includes utilization of atime value determined using a calibration that includes: initiating animage acquisition sequence; analyzing the resultant image; and modifyingan adjustment factor that impacts the value of a delay factor of theinstruction.
 114. A system for synchronizing a photographic lightingdevice to image acquisition by a camera having an image acquisitionsensor and a shutter system with a first shutter blade, the systemcomprising: a connection to a camera circuitry providing access to acamera predictor signal; a memory including information related toinstructions for initiating light emission after the first shutter bladebegins to expose the image acquisition sensor to light and before X-syncassociated with the first shutter blade stopping movement; a processorelement configured to use the information and the camera predictorsignal to generate a lighting emission initiation signal; and aconnection to the photographic lighting device in communication with theprocessing element for communicating the lighting emission initiationsignal to the photographic lighting device.